APK is an abbreviation for Android Package, the Android installation package (APK). APK file box Symbian Sis or Sisx file format is similar. Free APK files freedom apk and many more are passed directly to the Android emulator or Android phone, and then executed and installed. APK files and SIS, like, the Android Sdk compiled works packaged into an installation program file, the file format for the APK. APK file is a ZIP format of a compressed package, but the suffix is modified to APK, UnZip extract, we can see Dex file, Dex is Dalvik VMexecutes full name, that is, Android Dalvik implementation of the program, not Java ME bytes But Dalvik byte code. In the Android platform dalvikvm executable file is packaged into APK format, the final run will be decompressed by the loader and then get the compiled android manifest.xml file permission branch related security access, but still have a lot of restrictions, if you The APK file will be passed to the / system / app folder will find the implementation is not restricted. The installation of the file may not be this folder, and in the Android Rom system APK file default will be placed in this folder, they have root privileges.
Illustration: APK file for impression notes.
Second , the APK file like spotify premium apk
structure 1.META-INF \ (Note: Jar file can often see);
2.res \ (Note: storage resource file
directory ); 3.Android Manifest.xml (Note: program global configuration file) ;
4.classes.dex (Note: Dalvik bytecode);
5.resources.arsc (Note: compiled binary resource file).