(Being a step-by-step guide to creating a fully-functional Instagram-like iOS app
that’s ready to submit to the App Store)
This post will be a start-to-finish guide to building an iOS (iPhone/iPad) app that lets users create, modify and share photos to a gallery within the app. By the end of this book you should have an app that’s ready to submit to the app store (assuming you’ve got an account set up with Apple to do that – and we’ll provide some resources to help you with that as well).
Obviously the process of designing and coding a feature-rich photo management app from scratch can be a complicated and intensive process, even if the developer has years of software development experience. So instead, what we’ll be doing is leveraging some open-source code (code that is freely available for download and modification), along with a photo-sharing service called Ostetso (www.ostetso.com – also free to use for smaller projects) to create a fully functioning app in just a few hours. While you’ll need a fundamental understanding of coding in order to create your app, you can polish your skills by modifying the base code and adding in new functionality.
The open-source framework we’ll start with is called Share Pictures and if you want to see what it looks like once it’s been turned into an app you can download the compiled version of it from the App Store directly. It’s a fairly simple app that allows you to apply a few filters to photos taken either from your camera roll or directly from the camera, and if you’re using the camera you’ll even see the filters applied in real-time as you’re getting ready to shoot. Here’s a few screenshots of the Share Pictures app in action so you’ll have an idea of what you’ll be putting together:
Over the course of this book, we’ll download and configure the Share Pictures code to connect to the Ostetso service, we’ll show you how to modify the Share Pictures code to make it your own, and we’ll walk you through the process of running it on your iPhone or iPad.
Beyond that, we’ll discuss how you can then modify and extend this framework to create an app of your own. Maybe you want to create a variation on Instagram that’s only used by your friends. Maybe you want to have a photo-sharing app that’s exclusively for people exchanging photos of their dogs. We like dogs! Maybe you’ll use this as a starting point to create something that will eventually replace Facebook, Snapchat and Twitter (and make you a billionaire in the meantime). It’s up to you, and once you’ve got the basic app working you’ll be able to explore any direction you find interesting. By starting with the existing template we provide you’ll bypass a huge amount of development (and debugging!) work and get straight to an app that you know is functional, reliable, and ready to release to the App Store. Let’s get started!
2. GETTING STARTED
You’ll need the following things in order to do the development described in this document:
- An Apple Mac computer. This is the only way to develop software for iOS devices.
- OS X El Capitan. While not strictly required, your results may not match this guide if you use a different version of OS X.
- A device running iOS (iPhone, iPad, or iPod Touch). Xcode (Apple’s software development tool, which we’ll download next) includes a simulator for these devices, but unfortunately it doesn’t provide the necessary APIs for interacting with the camera on your laptop, so you’ll be limited in what you can test.
2.1. Downloading Xcode and Signing up as a Developer
Before you can begin working with iOS apps, you need to download the Xcode development environment from Apple. Start by downloading the latest version of Xcode from the App Store. If this is your first time using Xcode, CodeWithChris provides an introduction to Xcode 7 for beginners, and there are a variety of additional resources out there including, of course, Apple’s own documentation here.
If you eventually plan to release your app to the App Store you’ll also need to sign up as a Registered Apple Developer (do so by clicking here), which costs $99/year for an individual membership. But even if you choose not to register just yet, you can still use Xcode to build and test your app locally.
Again we’re not really going to go into great detail about developing apps from scratch in this document. There are already a huge number of resources on the web for doing this. Probably the best place to start if you would like more information on developing iOS apps is the iOS Developer Library.
2.2. Using the Terminal
In addition to working within the Xcode application, there are other things we’ll need to be doing that require using the Terminal app. If you’re not familiar with it, this is a way to more directly interact with your computer’s operating system using simple commands. While you don’t need to be an expert, you should at least be able to use Terminal to navigate the filesystem and run basic Unix commands such as cd, ls, and cat. If you need to brush up on your Unix/Terminal skills, Macworld UK offers a beginner-friendly guide that presents common shortcuts and commands. The Terminal application is available on every Mac, found in the standard Applications/Utilities folder.
3. THE SHARE PICTURES PROJECT
As mentioned, we’re going to be basing our photo-sharing app on the code framework called ‘Share Pictures’. So the first thing we need to do is download that source code. This code is hosted on GitHub, a website where people store code and can track changes to that source code across multiple developers. Not only does GitHub allow you to freely download the code stored there, you can even upload changes to that repository should you enhance or extend the code in a way that might benefit other users.
To download the code for the Share Pictures app, click here, then click the “Download ZIP” button on the right-hand side of the screen.
Uncompress the file by double clicking on it in the Finder and choose a location to place the contents of the folder. This will become our working directory while we modify the source code. We recommend creating a new folder in your Home or project directory called “Development” or “Code” and moving the folder there.
The Share Pictures app is only a part of what we need. Share Pictures uses functionality that can only be provided through separate (third-party) libraries, which we’ll do next.
4. INSTALLING ADDITIONAL LIBRARIES
Rather than download the source for these libraries like we did with the Share Pictures code, we’ll instead install them using a dependency management tool called CocoaPods. CocoaPods isn’t, by default, installed on OSX but it can be added using a simple terminal command. To install CocoaPods, open a Terminal window and enter the following command:
sudo gem install cocoapods
Since we used ‘sudo’ to specify that this command be run as an administrator, Terminal will ask for your password. After entering your password and pressing Enter, CocoaPods will install. When the installation completes, it will show “21 gems installed” followed by a command prompt.
4.1. Installing GPUImage
GPUImage is an open source framework for processing images and videos using a computer’s GPU. Share Pictures uses GPUImage to process images, apply filters, and perform modifications faster than traditional means.
The code for GPUImage is publicly available via GitHub along with installation instructions. The Share Pictures project is already set up to use GPUImage, although we still need to install the framework itself. In the Terminal window, navigate to the directory where you downloaded the Share Pictures project. (If you followed our advice above that would be something like ‘Development’ or ‘Code’. Once you’re there, run the following command:
This prompts CocoaPods to detect and install any dependencies (Podfiles) found in the current directory (This may take several minutes to complete). While GPUImage is currently the only dependency, Ostetso (which we’ll install next) will eventually be distributed as a CocoaPod as well.
At this point, you have everything you need to build an app capable of taking photos from your phone and applying image-processing effects. But we need to add in one more component that will provide us with the photo-sharing capability we want.
4.2. Downloading and Integrating the Ostetso SDK
Ostetso is a framework for sharing images with all users of an app. Ostetso is a social network for images, letting users share images while providing features common to this sort of community photo gallery. Ostetso makes up the “social” component of the app that we’re creating.
Unlike Share Pictures and GPUImage, Ostetso is not open source (although it is available for free to smaller projects). It’s also not a self-contained tool but rather a framework that makes use of a cloud service (a “Backend as a service” or BAAS) to manage users, store photos, etc.
Because of this, we won’t download the full Ostetso framework into our app like we did GPUImage. Instead, we’ll download only a small portion of code (the Ostetso SDK), which we’ll then use to authenticate our app with the Ostetso cloud service. It’s this cloud service – not the app itself – that does all of the heavy lifting.
You can learn about the functionality provided by the Ostetso SDK by visiting www.ostetso.com/sdk. You can also see Ostetso in action by checking out some of the apps provided by Ostetso’s partners.
For now, we’ll focus on integrating Ostetso into our Share Pictures app. Since the Ostetso SDK isn’t available via Cocoapods, there are a few additional steps we need to take in order to properly integrate it into our project.
First, click here to download the Ostetso SDK. It’s compressed into a ‘zip’ file so you’ll need to uncompress that (the easiest way is to just double-click on the ostetsoSDK.zip file in the Finder) which should leave you with a new directory named OstetsoSDK. Within that directory you’ll find two items: Ostetso.framework and Ostetso.bundle. Move these two items into the Ostetso directory that lives directly under the main directory of the Share Pictures code we downloaded earlier.
Okay, you should now have everything in place to build the app. Let’s do that next.
5. RUNNING THE APP ON YOUR IOS DEVICE OR COMPUTER
Open the SharePictures.xcworkspace file to launch Xcode. You can either double-click the file in Finder, press Command-O in Xcode and select the file in the file picker, or, if you’re still in the Terminal, just type:
The Xcode application should open and you’ll see something that looks like this:
You now have two different ways you can see the Share Pictures application in action. If you’ve got an iOS device (iPhone/iPad) and it’s connected to your computer, you can tell Xcode to launch Share Pictures directly on that device.
If you don’t have an iOS device available, you can still see how most things work by using Xcode’s built-in device simulator which will bring up a separate window on your computer that emulates the behavior of a specific iOS device.
For either method, choose the device you’d like to test to by selecting it from the drop-down menu at the top of the Xcode window:
Now, to run your app, press the Run button (the sideways triangle) in the top-left corner of the screen. This will launch the simulator if needed and then in turn launch the Share Pictures app. The main Share Pictures page should look something like this:
Go ahead and click on the ‘Photos’ button. Select an image from the Camera Roll. This opens the image in Share Pictures, where you can edit the image using a variety of effects and filters. Tap on each filter to view its effect, and use the slider on the right-hand side of the screen to change the intensity. You’ll see the effect applied to the image in real-time.
Let’s review what we’ve accomplished so far: we downloaded a base app called Share Pictures; we installed the GPUImage library (which lets us modify images in the app); and we’ve installed the Ostetso framework (which will allow users to showcase their images in a public gallery). And we’ve just tested the app in the simulator or on a device.
At this point you’ve you’ll probably notice that certain things still aren’t working in the app yet – for example the little ‘share’ button at the bottom of the screen that shows up once you’ve applied a filter to an image. And in fact if you try to go to the ‘gallery’ from either the home screen or the upper-right corner of this screen you’ll notice that’s not working either. This is because we haven’t yet configured the Ostetso framework, which we’ll talk about next.
6. CONFIGURING OSTETSO
Before you can see and share to the public gallery of images created by other Share Pictures users, you need to register and configure your app with/for the Ostetso service. This involves three steps: registering as an Ostetso developer, registering your specific app with Ostetso, and supplying your app with a key that it will use to authenticate with the Ostetso service while it’s running.
6.1. Registering as an Ostetso Developer
Create a new Ostetso account via the sign up page. After entering your account details, you will receive an email asking you to confirm your details. Click the link provided in the email, and your account will be activated.
6.1.1. Filling out the Ostetso App Information Form
After logging in to your account, you are taken to the Dashboard. The Dashboard displays a list of apps connected to your Ostetso account. Since your account is new, this list should be empty. To add a new app to your account, click the Add New App button.
Before you can register your app, you will need to provide basic information about the app such as the app name, the App Store URL (if available), the app’s website URL (if available), and contact information for the app’s owner. Not all of this information is required, and most of this information can be changed later. However, this would be a good opportunity to think of a unique name, since we’ll be changing the name from “Share Pictures” to something unique in the next section. – in fact, you can register an app even if you haven’t yet written a single line of code.
You’ll also notice that there’s already an App ID and an App Key shown which was generated during the creation of this new app. You’ll be adding these to the source code of your Share Pictures app shortly.
Once you’ve filled in your app details, press the Save button. You will be redirected to the Dashboard where you can see your new app listed. You’re actually going to be needing the App ID and App Key values In the next section, so go ahead and click on the View/Edit button for your app to return to the App Information page.
6.2. Adding your Ostetso Key to your app
By adding the App ID and App Key values into your app’s source code it will be able to communicate with the Ostetso service every time it runs.
Open Xcode and look for the OstetsoConfig.h file under the second SharePictures directory.
The values that we need to set are OSTETSO_APP_ID and OSTETSO_API_KEY, both of which currently contain placeholder values. Replace the values between the double quotes with your App ID and App Key values. Make sure you preserve the quotes and “@” symbol before the string values. For example,
#define OSTETSO_APP_ID @”PROVIDE YOUR APP ID HERE”
#define OSTETSO_APP_ID @”E42C6E41-2ACA-E95A-B1C4-C19C9CD0374C”
Rebuild your app and run it in the simulator or on your device.
6.3. Testing with Ostetso
Registering your app with Ostetso means you can now interact with Ostetso’s services such as uploading images and viewing images uploaded by other users. From the Share Pictures app home screen, click on Gallery. You can browse images from specific users and specific apps by tapping the buttons at the top of the screen.
You can also touch on any image in the two-column view and it will expand to be full-screen where you can see more information about the image, etc.
Note that the app is currently running in a sandboxed environment, so the only images you’ll see are those that have been uploaded by other Ostetso developers. The Sandbox environment is used for developing and testing apps, whereas apps that are ready for release to the App Store run in the Production environment. When an app is in Production, its images will become available to the general public.
Click the home icon in the top-left corner of the screen to return to the app’s home screen, then click Photos to browse your Camera Roll. Select a photo which will load it into your app, and then apply a filter (from the list of icons at the bottom) to it. Click on a filter to apply it, then drag the slider on the right-hand side to change the intensity of the filter. Once you’ve applied the effect you like, click the large Share button.
Since you haven’t logged in yet, the app will prompt you to do so. You should use the same credentials you used to register as an Ostetso developer. (You can create a new ID here instead if you wish, but it won’t have the same administrative privileges as your Ostetso developer ID).
Once you’ve logged in, you’ll be able to share your photos to the gallery (you can choose to make them ‘Private’ instead if you don’t wish to do that) and you can also share to a number of external services. The Sharing page should look something like this:
The Ostetso framework provides a variety of additional features related to image sharing as well as a rich set of administrative tools that you, as the owner of the app, can use to curate the user gallery. Please see the Ostetso SDK documentation for more information: https://www.ostetso.com/sdk.
7. ADVANCED OSTETSO FEATURES
Once you have the basic Ostetso functionality working within the Share Pictures app, you might consider extending the base feature set with a couple of additional features that Ostetso provides. Note that these features require you to have an app that’s been registered with Apple and thus they’re something you probably won’t be dealing with until you’ve worked through the next few sections. But we’re putting them here since they’re part of the Ostetso configuration.
7.1. Facebook Integration
Ostetso’s Facebook integration lets you easily share images between your app and Facebook. Images posted to Facebook are branded with your app’s name and link to your app in the App Store. When users click on the image, they’re taken to a dynamically generated web-page that also displays your app’s name and a link to the App Store.
For more information on Facebook integration, see the Facebook Configuration page in the Ostetso SDK.
7.2. Push Notifications
Push notifications let you send notifications to your users even when your app isn’t running. They’re an incredibly powerful way to make sure your users are aware of new content that they might find interesting within the app (if someone has ‘liked’ one of their photos, for instance) and judicious use of Push notifications can pull existing users back into the app rather than allowing them to forget about it.
The Ostetso service can manage these Push notifications for you, saving you additional coding and management time, You will need to configure your app settings on Apple’s developer site before you can make the service available to your users. For more information on how to enable push notifications for Ostetso, see the Push Notification Configuration page in the Ostetso SDK, and then for details on how to tell Apple that your iOS app is Push-enabled, see this Apple Developer resource.
8. MAKING THE APP YOUR OWN
Now you have a working app that successfully manages, modifies, and shares images. You’re almost ready for the App Store, but there are still some steps you need to take before you’re ready to publish. In particular, you’ll need to customize your app so it’s not just a complete clone of the Share Pictures application. First up – pick a new name!
8.1. Renaming Your App
While the name “Share Pictures” isn’t bad, you’ll likely want to change the name to something a bit more personal and unique. The name of your app is one of the first things your users will see, so be sure to choose one that’s both descriptive and memorable. (Also, be aware that Apple will prevent you from registering your app if an app with that exact same name is already in use). If you previously specified a name for your app when you registered with Ostetso then you’ll want to use that same name here.
To change the name of your app, select the root “SharePictures” directory in the project navigator (upper-left corner of the window) and then from the top menu select View > Utilities > Show File Inspector. This will make sure you’re able to see the file inspector in the right-hand side of the window.
Now, In the ‘Identity and Type’ area of the inspector, enter the new project name in the Name field.
For this example we’ll change the name of the app to be “MySharePictures” but feel free to come up with your own name, particularly if you’ve got some idea for what sort of app you’d ultimately like to create. Maybe you’ve decided you want to create an app that’s focused on letting people share close-up photos of of their own smiles. It’s maybe not the most imaginative app out there but getting people to smile is never a bad thing! So in that case you might want to name your app “ShareSmiles” instead. It’s entirely up to you at this point!
Once you’ve changed the name and hit <return>, a window will appear that lets you determine the areas of the app that will change to the new name. By default, everything in the project will change to the new name which is exactly what we want. Click Rename to rename your project.
At this point we’ve updated the name of our project in Xcode, but the app will still display “SharePictures” if you try to build it to your device. To fix this, we also need to change the app’s Display Name.
In the project navigator, open the Supporting Files folder underneath the Share Pictures folder. You’ll see a file called MySharePictures-Info.plist. Double click the file to open the editor, and change the value of “Bundle display name” from “SharePictures” to “MySharePictures. ” Close the file, then re-run the simulator to verify the changes.
8.2. Customizing your App’s icons
You’ve changed the name of your app in the previous section but you’ll probably also want to customize the app’s icon so it is different from the default Share Pictures icon. This is a more involved process than you might expect since in fact you’re going to need to generate a large number of images to satisfy the size/resolution requirements of all the different iOS devices that your app might run on. Many apps, including Share Pictures, also feature a Splash Screen (known as the Launch Image for iOS) that shows up for a few moments when you first launch the app.
This document isn’t intended to be a guide to designing icons – we’ll let you look around the web for some good resources along those lines. You should also go to the source and look through Apple’s iOS Human Interface Guidelines, specifically those related to Icon and Image Design (direct link to that section is here) in order to familiarize yourself with the different required resolutions needed.
The easiest way to generate all the images you’ll need is usually to design one ‘Master’ icon at high resolution and then use that to generate all the smaller icons you’ll need. You can do this manually or (as we recommend) by taking advantage of one of the myriad icon-generating tools that third-party developers provide. There are web-based tools, OSX tools, and iOS apps that all will take in a single high-resolution image (to be safe, start with something that’s at least 2048 pixels square) and with a click of a button spit out all the individual image files your app will require. www.makeappicon.com is one such tool that we’ve used (though they do require you to give them an email address in order to get your icons sent to you), but if you Google “generate iOS icons” you’ll find many others to choose from as well.
When adding images to your app, keep in mind that iOS automatically applies a mask that rounds off the corner of the icons. Apple recommends creating images with sharp 90 degree edges and limited detail around the corners so that the mask doesn’t crop off parts of the image. Incidentally, Apple will also require a larger version of your icon (1024×1024 pixels) for display in the App Store when you go to submit your app.
Once you’ve generated all the icons you need, you’ll use Xcode again to replace the existing Share Pictures icons. Open the Share Pictures app and click on the Images.xcassets resource under the Resources directory. You’ll notice that there are two resources listed: an app icon and a launch images. When you click on either resource, you’ll notice that they contain multiple variations of the same image. These versions correspond to the resolutions that iOS requires.
You’ll also notice that not all of the icon ‘slots’ are filled-in for Share Pictures. At the time this document was written iOS was sometimes, for certain resolutions, able to substitute a similar icon and still support all devices. You might also find, for example, that if you don’t plan to support iPad that you don’t need to generate certain assets for that.
But having said that, it’s usually very little work (particularly if you’re using one of the icon-generating tools as mentioned above) to generate all possible resolutions you might need and put them into your project.
To replace an existing image, simply drag the new image file from Finder onto the image you want to replace. How do you know which images go where? Apple doesn’t make this as clear as you’d think, but the way this works is to look at the specifier for the bin in question which will tell you the ‘Base Size’ of the image and then multiply that number by the ‘Multiplier’ value that’s shown directly below the icon. Here’s a diagram that should make that more clear.
You’ll also need to go through the same process to replace the Launch images for your app with your new artwork.
Once you’ve done all this, rebuild the project and launch it on your connected device (or the simulator) to compile the new images into your app and confirm that you’ve done everything properly.
8.3. Customizing the Gallery
While the Share Pictures app comes with its own default style, the Ostetso framework does allow you to customize the visual elements of that gallery to create a unique look and feel.
All of the visual elements that you can modify are listed in the Ostetso.h file in the Ostetso.framework bundle, under the section labeled “Ostetso User Interface Customization Settings.” This includes button colors, border styles, image icons, fonts, and spacing. In order to change the default value, call the corresponding method in your app at some point after initializing Ostetso with the setApplicationID() method.
For example, if you wanted to change the border color on each image in the gallery to dark red, add the following method to SPAppDelegate.m:
[Ostetso setGalleryBackgroundColor: [UIColor colorWithRed:0.4 green:0 blue:0 alpha:1]];
For more information, refer to the customization section of the Ostetso SDK documentation.
8.4. Applying and Modifying Filters
Thanks to the GPUImage integration, your app is already able to apply a small set of filters to an image but there are dozens of additional filters that GPUImage supports.
We will eventually be adding some more detailed instructions for how to create and modify image filters within the Share Pictures app but for now we’ll give you a few pointers and leave the rest as an exercise for the reader. Also, you might want to read through the GPUImage documentation at GitHub to understand everything that it’s capable of.
For Share Pictures, all of the effects are described/specified within the ‘effects’ folder shown here:
For each effect, you’ll need a few different files but the primary one is the effect description file, which ends with the .fx suffix.
So for example, the ‘Haze’ filter has a description file named Haze.fx. If you look within that file you’ll see that (among other things) there are specifiers for the name of the effect (as it will be shown within the app), the type of effect we’re using from GPUImage (in this case it’s a filter called GPUImageHazefilter), and the icons we’re using to choose the effect when you’re running Share Pictures.
9. PREPARING FOR RELEASE
Once you’ve modified your new app to contain all the features you want and you’re ready to submit it to the App Store, there are a few final steps you’ll need to take in order to tell the Ostetso service that you’re going to be submitting.
Specifically, we need to change the app’s Ostetso environment from ‘testing’ to ‘production’.
9.1. Changing the Ostetso Environment
As mentioned earlier, Ostetso places apps in one of two environments: Sandbox (the default for new apps), and Production.The Sandbox environment is used for developing and testing apps, while the Production environment is only for apps that are ready to send to the App Store. When an app is in Production, its images will be available to all of the app’s users through Ostetso.
Before you can run your app in production, it needs to be approved by Ostetso. Open your app configuration page on the Ostetso website and press the “Submit for promotion to production” button. Ostetso will review your app and will contact you via email once the process is complete. This process can take anywhere from one to five business days.
Once your app is approved, you can switch your app over to Production by changing the USE_PRODUCTION_SERVER variable to YES inside the OstetsoConfig.h file (the same place where you added the APP_ID and APP_KEY values earlier). So it should look like this:
#define USE_PRODUCTION_SERVER YES
10. SUBMITTING YOUR APP TO THE APP STORE
When your app is feature-complete and fully tested, it’s ready to hit the App Store. (And, remember, you need to be a paid Apple Developer before you can do this).
Make sure that your app passes the iTunes Connect validation test and meets the iOS Human Interface Guidelines. Also, make sure you review the App Store Review Guidelines.
Since the base Share Pictures app that’s provided on Github is a copy of the app that has already been approved by Apple, you’re unlikely to run into any problems with this unless you’ve modified things dramatically.
Apps are submitted to the App Store through iTunes Connect. iTunes Connect stores all of the metadata regarding your app such as the app version, build number, name, and category. iTunes Connect also provides tight integration with Xcode, allowing you to quickly and easily upload new builds.
10.1. Creating an iTunes Connect Record
Before you can create a build, you’ll need to create a Record for your app in iTunes Connect. Start by logging in to iTunes Connect using your iOS Developer Program account. Follow the instructions in the Creating an iTunes Connect Record for an App article, making sure to select iOS for your platform. If you want to add additional features such as in-app purchases, GameCenter, or other Apple services, be sure to read the article Configuring Store Technologies. You might also want to use TestFlight to beta test your app before releasing it to the public. We’ll explain how to use TestFlight later in this guide.
10.2. Uploading a Build through Xcode
There are two ways to upload a build to iTunes Connect: Xcode and Application Loader. We’ll upload our app using Xcode, since it’s already tightly integrated with iTunes Connect. Follow the instructions in the Submiting Your App section of the App Distribution Guide. This guides you through the process of configuring your app’s settings, uploading a valid archive to iTunes Connect, and submitting the app for review. The last step is App Review, where Apple reviews and verifies whether your app is ready for the App Store.
10.3. Testing using TestFlight
Testing your app is an opportunity for you to discover and resolve any bugs, shortcomings, or overlooked areas of your app that you wouldn’t have otherwise noticed. It gives you the chance to polish your app, improve the first impressions of your users, and increase sales.
TestFlight is a service that lets you pre-release your app to select users. You can distribute your app to specific users and receive feedback before releasing it to the general public. If you haven’t already, create an iTunes Connect Record and upload a build by following the instructions above.
10.3.1. Adding Testflight Users
TestFlight categorizes users into two groups: internal and external. Internal testers are users who have access to your organization’s content in iTunes Connect and have been assigned the Technical or Admin role. You can invite up to 25 internal testers, and each tester can test on up to 10 devices. External testers are users who aren’t a part of your organization, but who you can still invite to test your app and provide feedback. You can invite up to 2,000 external testers, although your app must conform to the App Store Review Guidelines before it will be distributed to them.
To invite internal testers, open the TestFlight pane in iTunes Connect then click Internal Testing. Click the plus sign (+) to add new testers, then click Add. Adding external testers is a similar process, except you’re required to provide the name and email address of your target users. Note that before you can invite external testers, your build to be approved by Beta App Review.
If testing is limited to users on your team (internal testers), you won’t have to enter any metadata about your app beyond the basic required information. However, if you want to include users outside of your team (external testers), you will need to provide the following additional information:
- What to test
- App description
- Feedback email
- Marketing URL
- Support URL
- Beta App Review contact information
- Beta App Review notes (optional)
You can add or edit metadata by opening the App Details page, clicking Activity, clicking All Builds, then clicking the build number used for testing.
10.3.2. Enabling Testing
To enable testing, click on the TestFlight pane in iTunes Connect. Select the build that you want to test, then click Start Testing. Your users will receive an invitation via email. When they receive their invitations, they’re prompted to download the TestFlight app onto their iOS device.
The TestFlight app is a centralized location for installing test apps, providing feedback, and notifying users of new builds. Users can test your app for a period of 60 days following the release date.
After reviewing and integrating the feedback provided by your beta testers, your app is ready to submit to App Review and eventually make its way onto the App Store.
Congratulations, if everything went smoothly you’ve now got your very own photo-sharing app. Now go out into the world and crush Instagram! (Or at least have some fun seeing all the fun imagery your users are sharing and creating).
We’d love to hear about your experience working through the process, about the Ostetso service, and about this guide in general. Was this information provided useful and accurate? If there’s something that we got wrong, or didn’t explain fully, please let us know! You can reach us at email@example.com.
Or just drop us a note to say ‘hi’, and tell us about the app you’ve created. (Seriously, please do this – we really want to hear about what people are doing!)
 And, just in case it wasn’t totally clear, this book was written by the same team that created the Ostetso service and who also wrote the majority of the Share Pictures app before releasing it to the public. We created the Ostetso service because we feel that sharing photos with your friends is a wonderful thing and we want to make it easier for people to do that. We hope this book and the Ostetso framework helps you, as a developer, to create your own awesome photo-sharing apps!
 A dependency is code that your software needs to perform a function. Dependency managers let you easily manage multiple dependencies.
 If you’ve done any previous development using xCode you probably started by selecting a .xcodeproj file but that changes once you start using CocoaPods, which requires you to use the .xcworkspace file instead.
 Also, if you’re running in the simulator the Camera button will work but you’ll only see a white screen instead of the output of a camera. This is normal – to test any sort of camera functionality you’ll need to be running on an actual iOS device.
 For more information on the different app environments, see the Changing the Ostetso Environmentsection.