How to build Android

📌 Installation: Make sure all the correct modules are installed. Open Unity Hub, select a version of unity, select add modules, install Android Build Support, and be sure to toggle subfields Android SDK, NDK, and OpenJDK.
📌 If you run into any issues with the SDK path, you can always download and set the paths manually in the Preferences → External Tools.
📌 Target Android by going to File → Build Settings and switching your active target to Android.
📌 Player Settings will need to be set. Fill your company and product name. The version should be something like "1.0.0".
📌 Default Icon will be used if no other icons are set. However, you can easily set the icons for Adaptive, Round, and Legacy. Just drag an image into the highest resolution and Unity will automatically generate the lower resolution icons.
📌 Prevent your app for rotating to portrait or landscape inside the Resolution and Presentation settings. More global app settings can be found here.
📌 Other Settings contains the SDK version and graphics settings. It's here where you will define what graphics API's are supported, the minimum API level, and much more. Familiarize yourself with these settings because they'll determine what devices your game can run on and even how they will perform.
📌 Publish Settings - If you wish to upload to Google Play or Oculus, you'll need to use a custom keystore. Google Play has a feature that will automatically sign when you upload your APK, however, I still like to create my own keystore. This is easily done inside of Unity, just open Keystore Manager, and create a new keystore.
📌 Testing in Editor while targeting Android is very important. It is your first line of defense for detecting platform-specific issues. When targeting Android, platform-specific C# code will be compiled for Android, while code wrapped in directives like UNITY_IOS, will not be compiled.
📌 Build and deploy directly to a device within the build settings. Make sure Export Project is disabled, and you can build directly to an APK.
📌 When export project is enabled, it will not build an APK, but instead, create an Android Studio project. This is good for more advanced build pipelines, where you can not set all your desired settings in the Unity post-build scripts.

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