| APK | |
|---|---|
.png){kind=icon} | |
| Filename extension | .apk,.apks,.aab,.xapk,.apkm,.akp |
| Internet media type | application/vnd.android.package-archive |
| Type of format | Package format |
| Container for |
|
| Extended from | JAR |
TheAndroid Package with the file extensionapk[1] is thefile format used by theAndroid operating system and a number of other Android-based operating systems for distribution and installation ofmobile apps,mobile games andmiddleware. A file using this format can be built from source code written in eitherJava orKotlin.
APK files can be generated and signed fromAndroid App Bundles.[2]
APK is analogous to othersoftware packages such asAPPX inMicrosoft Windows,APP forHarmonyOS or aDebian package inDebian-based operating systems. To make an APK file, a program for Android is first compiled using a tool such asAndroid Studio[3] orVisual Studio and then all of its parts are packaged into one container file. An APK file contains all of a program's code (such as.dex files), resources, assets, certificates, andmanifest file. As is the case with many file formats, APK files can have any desired name but, for the system to recognize them, the .apk filename suffix may be necessary.[4]
Most Android implementations allow users to manually install APK files (sideloading) only after they turn on an "Unknown Sources" setting that allows installation from sources other than trusted ones likeGoogle Play. One may do so for many reasons, such as during the development of apps, to install apps not found on the store, or to install an older version of an existing app.[5]
TheQNX-basedBlackBerry 10 included an Android runtime environment; initially, apps were required to be packaged in the operating system's native format, and installed via theBlackBerry World app store or sideloading.[6] Beginning on BlackBerry 10.2.1, the operating system added support for sideloading APK files directly.[7][8]
AtBuild 2015,Microsoft announced an Android runtime environment forWindows 10 Mobile codenamed "Astoria" (later renamedWindows Bridge for Android), which would allow Android apps to run in an emulated environment with minimal changes, and have access to Microsoft platform APIs such asBing Maps andXbox Live as nearly drop-in replacements for equivalentGoogle Mobile Services. Google Mobile Services and certain core APIs would not be available, and apps with "deep integration into background tasks" were said to poorly support the environment.[9][10] On February 25, 2016, after already having delayed it in November 2015,[11][12] Microsoft announced that Windows Bridge for Android would be shelved, in favor of focusing on Windows Bridge foriOS (a native implementation of the iOSObjective-C APIs, which allowsXcode projects to be converted toVisual Studio projects targeting Windows platforms) and cross-platform development using theC# language instead.[13][14] Portions of Astoria were used as a basis forWindows Subsystem for Linux (WSL) on the PC version of Windows 10.[15]
On August 9, 2019,HarmonyOS came with APK compatibility viaAOSP base withLinux kernel on HarmonyOS 1.0 for TVs and also June 2, 2021,HarmonyOS 2.0 version expanded to smartphones and tablets until Galaxy Edition version underHarmonyOS NEXT system for the next iterative HarmonyOS 5 beta to commercial version, starting in November 26, 2024 stable, officially dropping APK support.[16][17][18][19][20]
In June 2021, Microsoft announced the "Windows Subsystem for Android" (WSA), an AOSP-based layer for sideloading Android apps onWindows 11. The software utilized a runtime compiler developed byIntel, and apps could be sideloaded, published viaMicrosoft Store, or obtained via an Amazon Appstore client.[21][22][23] In March 2024, Microsoft announced that WSA would be deprecated and discontinued in March 2025.[24]
An APK file is aZIP archive that usually contains the following files and directories:
META-INF directory:MANIFEST.MF: theManifest fileCERT.SF: The list of resources and aSHA-1digest of the corresponding lines in the MANIFEST.MF file; for example:Signature-Version: 1.0Created-By: 1.0 (Android)SHA1-Digest-Manifest: wxqnEAI0UA5nO5QJ8CGMwjkGGWE=...Name: res/layout/exchange_component_back_bottom.xmlSHA1-Digest: eACjMjESj7Zkf0cBFTZ0nqWrt7w=Name: res/drawable-hdpi/icon.pngSHA1-Digest: DGEqylP8W0n0iV/ZzBx3MW0WGCA=
lib: the directory containing the compiled code that is platform dependent, for example native libraries that can be loaded throughJNI; the directory is split into more directories within it:res: the directory containing resources not compiled into resources.arsc (see below).assets: a directory containing applications assets, which can be retrieved byAssetManager.AndroidManifest.xml: An additional Android manifest file, describing the name, version, access rights, referenced library files for the application. This file may be in Androidbinary XML that can be converted into human-readable plaintext XML with tools such as AXMLPrinter2, Apktool M, or Androguard.classes.dex: The classes compiled in thedex file format executed byAndroid Runtime (or byDalvik virtual machine used inAndroid 4.4 KitKat).resources.arsc: a file containing precompiled resources, such as binary XML, for example.Note: Historically the NDK supported ARMv5 (armeabi), and 32-bit and 64-bitMIPS, but support for these ABIs was removed in NDK r17.
Support for ARMv5 (armeabi), MIPS, and MIPS64 has been removed. Attempting to build any of theseABIs will result in an error.
| Archiving only | |
|---|---|
| Compressing only | |
| Archiving and compressing | |
| Software packaging and distributing | |
| Document packaging and distributing | |
