Android phones, like the
Galaxy Nexus, allow installation of applications directly via APK files or indirectly via
Google Play
Android application package file (APK) is the file format used to distribute and install application software and middleware onto Google's Android operating system. To make an APK file, a program for Android is first compiled, and then all of its parts are packaged into one file. An APK file contains all of that program's code (such as .dex files), resources, assets, certificates, and manifest file. As is the case with many file formats, APK files can have any name needed, provided that the file name ends in ".apk".[1][2][3][4]
APK files are ZIP file formatted packages based on the JAR file format, with .apk file extensions. The MIME type associated with APK files is application/vnd.android.package-archive.[5]
Contents [edit]
An APK file is an archive that usually contains the following folders:
META-INF directory:
MANIFEST.MF: the Manifest fileCERT.RSA: The certificate of the application.CERT.SF: The list of resources and SHA-1 digest; for example:
Signature-Version: 1.0
Created-By: 1.0 (Android)
SHA1-Digest-Manifest: wxqnEAI0UA5nO5QJ8CGMwjkGGWE=
...
Name: res/layout/exchange_component_back_bottom.xml
SHA1-Digest: eACjMjESj7Zkf0cBFTZ0nqWrt7w=
...
Name: res/drawable-hdpi/icon.png
SHA1-Digest: DGEqylP8W0n0iV/ZzBx3MW0WGCA=
lib: the directory containing the compiled code that is specific to a software layer of a processor, the folder is split into more folders within it:
armeabi: compiled code for all ARM based processors onlyarmeabi-v7a: compiled code for all ARMv7 and above based processors onlyx86: compiled code for x86 processors onlymips: compiled code for MIPS processors only
res: the directory containing resources not compiled into resources.arsc (see below).assets: a directory containing applications assets, which can be retrieved by AssetManager.AndroidManifest.xml: An additional Android manifest file, describing the name, version, access rights, referenced library files for the application. This file may be in Android binary XML that can be converted into human-readable plaintext XML with tools such as AXMLPrinter2, apktool, or Androguard.classes.dex: The classes compiled in the dex file format understandable by the Dalvik virtual machineresources.arsc : a file containing pre-compiled resources, such as binary XML for example.
See also [edit]
References [edit]
