Build types
Applications have to be signed with a private key when they are built. An application can't be installed in a device or even in the emulator if it is not signed. To build our application, there are two types: debug and release. Both APK versions contain the same folders and compiled files; the difference is in the key used to sign them. Both modes are explained as follows:
Debug: When we ran and tested our application in the previous chapters, we were in debug mode, but we didn't have a key nor did we do anything to sign our application. The Android SDK tools automatically create a debug key, an alias, and their passwords to sign the APK. This process occurs when we are running or debugging our application with Android Studio without us realizing. We can't publish an APK signed with the debug key created by the SDK tools.
Release: When we distribute our application, we have to build a release version. Google Play requires the APK file to be signed with a certificate, for which...
