JADX - JADX is a decompilation tool that can produce Java Source code from Dex and Apk files, being capable of providing human-readable java classes, it reverses AndroidManifest.
Apktool - Apktool is an all-in-one tool that can extract all the resources inside an APK.
Xposed Framework - Xposed Framework is an application that allows you to tweak and modify the Android system behavior without making changes to system apps.
JEB - JEB is an Android application decompiling tool that allows you to inspect and modify APKs.
TTDeDroid - TTDeDroid is an open-source application that lets you decompile Android applications, including APK, JAR, AAR, and DEX formats.
APKInspector - APKInspector is an open-source application that you can use to lookup the Android APK information and get the app insights.