Code Signing In iOS Applications
Code signing becomes very significant when you install your iOS application on the actual device. All iOS apps that run on the device must be signed by the developer which requires a valid certification from Apple.
The process of signing your build is required regardless of which iOS device you intend to install your application which makes the code signing process the most challenging part of iOS app distribution.
Let us take a closer look at the fundamentals and process of code signing iOS Applications.
What is Code Signing in iOS?
Code signing is a method of ensuring that an iOS app is installed from a trusted source. It indicates that the developer’s source code has not changed since it was last signed by an authorized developer. It is the same as when we sign a contract with someone in real life.
What's the Importance of Code Signing in iOS?
There are various benefits for Code Signing iOS applications. Let us know some of the main benefits:
It assures that your iOS application is from a secure source.
Code signing depicts that the content of the app has not been changed since last signed.
It helps organizations build trust with clients.
Code signing helps you to safely distribute your application.
It enables Apple to control what apps can be installed on iOS devices.
If you do not digitally sign applications, you will be only able to run your code on jailbroken device or simulator.
You cannot reach a wide audience without iOS Code Signing. You can even work without code singing, but this can be useful for initial testing purposes, hence it is not enough to reach your targeted audience.
Enables developers to distribute apps on more platforms.
Helps you verify the application with Apple.
Methodology of Code Signing and Publishing iOS Applications
We will discuss a commonly used utility tool called "iOS Gateway" for building iPhone OS apps. This is quite an impressive and easy way to digitally sign iOS Applications.
What is iOS Gateway?
iOS Gateway is a free application that can be easily connected to Eggplant Functional with your iOS devices. It enables you to control iOS device operating systems ranging from iOS 10 to iOS 14. If you have an iPad with OS 13, an iPad with OS 14, or an Apple TV, this app will also give you the expected result.
iPhone OS works on Gateway VNC (Virtual Network Computing) server. When you connect your PC from Eggplant functional, you can actually see and control your iOS device. It is not mandatory that the Mac where this iOS Gateway is running does not require to be exactly the same as where you have installed Eggplant functional. However, you must connect your iOS device to a USB port where iOS Gateway is installed.
Signing Prerequisites
For any iOS App Code Signing, you should have some basic components which are mandatorily required without which you won't be able to do the signing process.
A .ipa File: It is the iOS application archive of the app that you are going to sign.
Code Signing Certificate: It's usually a code signing certificate that can be used for development purposes. This certificate is issued through either the Xcode or Apple Developer Portal website.
App ID: You need an app ID, the identifier is associated with the app you would like to install. You have to create a development provisioning profile that is created on the website of Apple Developer.
Provisioning Profile: Provisioning profile allows your signing app to run with Xocde IDE for development use. It is created through this IDE or Apple Developer portal website.
Developer-Enabled: iOS Device: Apart from the components discussed above, you may need a developer-enabled iOS device, listed in your Apple Developer portal.
iOS Code Signing Using iOS Gateway
iOS Gateway is a very popular tool for code signing iOS apps and it has a user-friendly IDE. If you are looking to perform automatic code signing using the signing utility available in iOS Gateway, you may follow these easy-step tutorials:
Step 1: Navigate to Apps > Sign App. This will open the "Sign App" panel.
Step 2: In the Original IPA field, mention the .ipa file path of the app you want to sign. For this, you can simply drag and drop your application file into this field or you can click the “Browse” button to find your file.
Step 3: You need to again mention the path for the mobile provisioning profile under Apple Developer Center. Now, you have to either drag and drop your app file into this field or click the “Browse” button to find your file.
Step 4: Choose the code signing in simple terms the signing certificate from the dropdown. This is needed for signing the iPhone OS app.
Step 5: Additional Option checkbox. As mentioned, it is additional and this checkbox can be checked if you are going to simulate some good security options like touch ID or Face ID.
Step 6: Click the “Sign” button. One copy of the .ipa file you have specified will be saved with -the resigned in the same location as the original .ipa file.
Step 7: Congratulations! You have successfully code signed your iOS app with iOS Gateway. You are ready to submit an application to the iOS app store.
Moreover, iOS App Code Signing using Gateway needs "Xcode IDE" on PC running iOS Gateway, but say if you are using an older version of iOS and macOS, compared to the recommended version, then you will be required to switch active version of Xcode which can be done using the below steps.
Step 1: Open "Xcode IDE"
Step 2: Navigate to Xcode >> Preferences >> Locations
Step 3: Go to the "Command Line Tools" dropdown menu and choose the Xcode version you have to activate.
Step 4: On the screen, enter the administrator password.
Step 5: Final step is close Xcode.
Other Ways to Digitally Sign iOS Apps
If you do not wish to sign your iOS app using iOS Gateway, then you can choose another method which is through "Automatic Code Signing" which means automatically provisioning available profiles on the Apple Developer portal account.
There are several platforms for code signing iOS code automatically, of which "Bitrise" is a highly useful and popular platform. It is a CI/CD (Continuous Integration and Delivery) Paas (Platform as a Service) that is developed for mobile app development. This mobile DevOps platform helps you to build, test, and deploy your iOS apps in an easy and quick manner.
Conclusion
To sum up, it is clear how to code sign iOS applications. Moreover, the signing process is a crucial part of app development and is mandatory before publishing any application on iOS platforms. Digitally signing the code ensures that the iOS app is installed from a trusted source on the device.