If you're looking to find out if an APK is 32 or 64 bit, there are a few ways to do it. The easiest way is to open the APK and check the lib directory to see which architectures are compatible. If there is no lib directory, it means the APK is compatible with all architectures. You can also inspect the structure of the APK file to check for 64-bit libraries.
Once created, the APK will be packaged with all the native libraries needed by the application. These native libraries are stored in several ABI-based folders. If you see “64” in the name of the architecture, you can guarantee that it's a 64-bit device. To find out if it's ARM or x86, check back to the Instruction Set section and look for the basic information such as the letters “arm”.
You can also use an app called Droid Hardware Info which is available on the Play Store and will tell you everything you need to know about your phone. Unity recommends that you upgrade to the latest LTS version of their editor to have access to the latest features and updates. If you're using a version of Unity that supports 64-bit Android libraries, you can generate a 64-bit version of your application by adjusting the build settings. If one of your APKs is marked as not compatible, but is older and cannot be enforced, one strategy is to add a maxSdkVersion%3D 27 attribute to the uses-dk element of that APK's manifest.
However, you should understand that this will only cover the building code and the libraries that you can create from the source code. Contact the owner of the SDK or library if a 64-bit version is not available and keep this in mind when planning compatibility with 64-bit devices. Play Console will also display warnings applicable to your pre-release versions if there are any issues related to the 64-bit requirement. Follow Unity's instructions to reduce the size of the APK and consider taking advantage of the Android app bundle feature to help mitigate this increase in size. The good news is that once you discover this information once, you shouldn't have to worry about it again until you have a new phone. And thankfully, with these tips, it's easy to identify if an APK is 32 or 64 bit.
