Mobile build (Android/iOS) in Unity - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the first step to prepare a Unity project for an Android build?

Open the Build Settings in Unity, select Android as the target platform, and click 'Switch Platform' to prepare the project for Android.

beginner

Which file format does Unity generate for Android builds?

Unity generates an APK (Android Package) file or an AAB (Android App Bundle) file for Android builds.

intermediate

What is the role of the 'Player Settings' in Unity when building for iOS?

Player Settings allow you to configure app details like bundle identifier, version, orientation, and permissions needed for the iOS build.

intermediate

Why do you need Xcode when building a Unity project for iOS?

Unity exports the iOS project, but Xcode is required to compile, sign, and deploy the app to an iOS device or the App Store.

intermediate

What is a keystore in Android builds, and why is it important?

A keystore is a file that holds security keys used to sign your Android app. Signing is required to publish the app on the Google Play Store.

Which Unity menu do you use to change the build target to iOS?

A Assets > Import Package

B File > Build Settings

C Window > Package Manager

D Edit > Preferences

The Build Settings window is where you select and switch the build target platform.

What file does Unity generate for an Android build by default?

A .ipa

B .exe

C .apk

D .app

Unity generates an APK file for Android builds by default.

Which tool is required to compile and deploy an iOS app built with Unity?

A Eclipse

B Visual Studio

C Android Studio

D Xcode

Xcode is Apple's official IDE used to compile and deploy iOS apps.

What must you configure in Player Settings before building for mobile platforms?

A Bundle Identifier and permissions

B Only graphics quality

C Screen resolution only

D None, defaults are fine

Bundle Identifier and permissions are essential for mobile app identity and functionality.

Why is signing an Android app with a keystore necessary?

A To verify the app's author and allow publishing

B To compress the app size

C To enable debugging

D To change the app icon

Signing verifies the app's author and is required to publish on Google Play.

Describe the steps to build and deploy a Unity project to an Android device.

Think about platform selection, app identity, signing, and deployment.

Explain why Xcode is necessary for building Unity projects for iOS and what role it plays.

Consider the difference between Unity export and final app creation.

Practice

1. What is the main purpose of the Build Settings window in Unity when creating a mobile app?

easy

A. To write the game code for mobile devices

B. To switch the platform to Android or iOS and start the build process

C. To design the user interface of the app

D. To test the app on a desktop computer

Solution

1. Step 1: Understand Build Settings role

   The Build Settings window lets you choose the target platform like Android or iOS for your app.

2. Step 2: Recognize build initiation

   It also allows you to start building the app file for the selected platform.

3. Final Answer:

   To switch the platform to Android or iOS and start the build process -> Option B

4. Quick Check:

   Build Settings = Platform switch + build start [OK]

Hint: Build Settings = choose platform + build app [OK]

Common Mistakes:

• Confusing Build Settings with coding or UI design
• Thinking Build Settings is for testing only
• Assuming Build Settings runs the app on desktop

2. Which of the following is the correct way to switch your Unity project to Android platform?

easy

A. File > Build Settings > Select Android > Click Switch Platform

B. Edit > Preferences > Android > Enable

C. Window > Android > Activate

D. Assets > Import Package > Android

Solution

1. Step 1: Locate platform switch option

   In Unity, switching platform is done via File menu, then Build Settings window.

2. Step 2: Select Android and switch

   Inside Build Settings, you select Android and click the Switch Platform button to change.

3. Final Answer:

   File > Build Settings > Select Android > Click Switch Platform -> Option A

4. Quick Check:

   Switch platform = Build Settings > Android > Switch [OK]

Hint: Switch platform only in Build Settings window [OK]

Common Mistakes:

• Trying to switch platform in Preferences or Window menus
• Importing packages instead of switching platform
• Assuming Android is enabled by default

3. Consider this Unity C# snippet for building an Android app:

BuildPlayerOptions buildPlayerOptions = new BuildPlayerOptions();
buildPlayerOptions.scenes = new[] {"Assets/Scenes/Main.unity"};
buildPlayerOptions.locationPathName = "Builds/Android/MyGame.apk";
buildPlayerOptions.target = BuildTarget.Android;
BuildPipeline.BuildPlayer(buildPlayerOptions);

What will this code do when run inside the Unity Editor?

medium

A. Do nothing because BuildPipeline.BuildPlayer requires more parameters

B. Throw a compile error because BuildTarget.Android is invalid

C. Build an iOS app instead of Android

D. Create an Android APK file at Builds/Android/MyGame.apk including the Main scene

Solution

1. Step 1: Analyze BuildPlayerOptions setup

   The code sets scenes to include Main.unity and output path to Builds/Android/MyGame.apk targeting Android platform.

2. Step 2: Understand BuildPipeline.BuildPlayer effect

   Calling BuildPipeline.BuildPlayer with these options builds the Android APK file at the specified location.

3. Final Answer:

   Create an Android APK file at Builds/Android/MyGame.apk including the Main scene -> Option D

4. Quick Check:

   BuildPlayerOptions + BuildTarget.Android = Android APK build [OK]

Hint: BuildPipeline.BuildPlayer + BuildTarget.Android = Android APK build [OK]

Common Mistakes:

• Confusing BuildTarget.Android with iOS
• Thinking BuildPipeline.BuildPlayer needs more parameters
• Assuming code throws compile errors

4. You tried to build an iOS app but got an error: "Xcode project not found." What is the most likely cause?

medium

A. Your Unity version does not support iOS builds

B. You forgot to install Android SDK

C. You did not switch the platform to iOS in Build Settings before building

D. You did not connect an iOS device to your computer

Solution

1. Step 1: Understand iOS build requirements

   Unity requires switching platform to iOS in Build Settings to generate an Xcode project.

2. Step 2: Identify cause of missing Xcode project

   If platform is not switched, Unity won't create the Xcode project, causing the error.

3. Final Answer:

   You did not switch the platform to iOS in Build Settings before building -> Option C

4. Quick Check:

   Missing Xcode project = platform not switched to iOS [OK]

Hint: Always switch platform to iOS before building for iOS [OK]

Common Mistakes:

• Confusing Android SDK with iOS build errors
• Assuming Unity version lacks iOS support
• Thinking device connection affects project generation

5. You want to build a Unity app that works on both Android and iOS devices. Which approach is best to manage builds efficiently?

hard

A. Use Build Settings to switch platform and build each app from the same project

B. Build for Android and rename the APK file to .ipa for iOS

C. Write platform-specific code only and build once for Android

D. Maintain separate Unity projects for Android and iOS

Solution

1. Step 1: Understand Unity multi-platform support

   Unity allows building for multiple platforms from the same project by switching platform in Build Settings.

2. Step 2: Evaluate build management options

   Maintaining one project and switching platform is efficient and avoids duplicate work, unlike separate projects or incorrect file renaming.

3. Final Answer:

   Use Build Settings to switch platform and build each app from the same project -> Option A

4. Quick Check:

   One project + switch platform = efficient multi-platform build [OK]

Hint: One project, switch platform in Build Settings for each build [OK]

Common Mistakes:

• Creating separate projects wastes time and causes sync issues
• Renaming APK to IPA does not create a valid iOS app
• Building only for Android ignores iOS requirements