Device api level android

Android API Levels

This is an overview of all Android versions and their corresponding identifiers for Android developers. Anyone is welcome to open an issue or pull request. Happy developing!

Version	SDK / API level	Version code	Codename	Cumulative usage 1	Year
Android 12	Level 31	S	Snow Cone 2	No data	2021
Android 11	Level 30	R	Red Velvet Cake 2	33.3%	2020
	targetSdk must be 30+ for new apps by August 2021 and app updates by November 2021.
Android 10	Level 29	Q	Quince Tart 2	61.9%	2019
	targetSdk must now be 29+ for all app updates.
Android 9	Level 28	P	Pie	76.2%	2018
Android 8	Level 27 Android 8.1	O_MR1	Oreo	83.9%	2017
	Level 26 Android 8.0	O		87.2%
Android 7	Level 25 Android 7.1	N_MR1	Nougat	89.3%	2016
	Level 24 Android 7.0	N		92.4%
Android 6	Level 23	M	Marshmallow	96.0%	2015
Android 5	Level 22 Android 5.1	LOLLIPOP_MR1	Lollipop	98.2%	2015
	Level 21 Android 5.0	LOLLIPOP , L		98.6%	2014
	Jetpack Compose requires a minSdk of 21 or higher.
Android 4	Level 19 3 Android 4.4	KITKAT	KitKat	99.6%	2013
	Google Play services do not support Android versions below API level 19.
	Level 18 Android 4.3	JELLYBEAN_MR2	Jelly Bean	No data
	Level 17 Android 4.2	JELLYBEAN_MR1			2012
	Level 16 Android 4.1	JELLYBEAN
	Level 15 Android 4.0.3 – 4.0.4	ICE_CREAM_SANDWICH_MR1	Ice Cream Sandwich		2011
	Level 14 Android 4.0.1 – 4.0.2	ICE_CREAM_SANDWICH
Android 3	Level 13 Android 3.2	HONEYCOMB_MR2	Honeycomb
	Level 12 Android 3.1	HONEYCOMB_MR1
	Level 11 Android 3.0	HONEYCOMB
Android 2	Level 10 Android 2.3.3 – 2.3.7	GINGERBREAD_MR1	Gingerbread
	Level 9 Android 2.3.0 – 2.3.2	GINGERBREAD			2010
	Level 8 Android 2.2	FROYO	Froyo
	Level 7 Android 2.1	ECLAIR_MR1	Eclair
	Level 6 Android 2.0.1	ECLAIR_0_1			2009
	Level 5 Android 2.0	ECLAIR
Android 1	Level 4 Android 1.6	DONUT	Donut
	Level 3 Android 1.5	CUPCAKE	Cupcake
	Level 2 Android 1.1	BASE_1_1	None
	Level 1 Android 1.0	BASE			2008

Definitions

• minSdk (Kotlin) / minSdkVersion (Groovy): The minimum SDK version your app will support, defined in build.gradle . For example, if your minSdk is 26, this SDK version corresponse to API Level 26 and Android 8, so your app will only run on devices with Android 8 or higher.
• targetSdk (Kotlin) / targetSdkVersion (Groovy): The SDK version that your app targets, defined in build.gradle . This should always be the same as compileSdk .
• compileSdk (Kotlin) / compileSdkVersion (Groovy): The SDK version that your app compiles against, defined in build.gradle . Android Studio uses this SDK version to build your AABs and APKs. This should always be the same as targetSdk .

Notes

Cumulative usage distribution figures were last updated on November 3, 2021 using data from Statcounter GlobalStats. These figures may have changed significantly since the last update. You may update the figures yourself with a pull request. ↩

The codenames for Android 10 and above in the table are the internal codenames. Beginning with Android 10, Google dropped the usage of codenames publicly.

API Level 20 is missing from the table because it matches Android 4.4W, the version that makes Android available for Android Wear. ↩

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Android API Level, backward and forward compatibility

Jun 9, 2019 · 8 min read

If you get to read this article it might mean you are wondering things like:

• What is an API?
• What does API Level mean?
• How to use compileSdkVersion, minSdkVersionor targetSdkVersion?
• How can I ensure my app will work properly on devices with different versions of the OS?

All these concepts are related to each other and I will try to clarify them to you in this article in a simple but effective way.

In order to do so, we need to have in mind the difference between SDK and API in software development and the meaning of API Level in the Android ecosystem.

In Android, it’s true that th e re is a 1:1 relationship between the SDK and the API and often these two terms are used as synonymous, but it’s important to understand they are not the same thing.
But it’s correct to say that for each Android version there is an SDK and there is an equivalent API and API Level.

It stands for Software Development Kit. Think of the word “kit”… it is exactly a collection or a set of different tools, libraries, documentation, samples to help developers to build, debug and run Android apps. Along with an SDK, an API is provided.

Opening the SDK Manager in Android Studio shows much clearer what is part of an Android SDK.
The first tab SDK Platform lists the SDKs of each Android version.
As per example, shown in the picture below, Android 9.0 (aka Pie) SDK contains:

• Android SDK Platform 28 (that’s the framework API)
• Source code for Android 28 (that’s the implementation of the API, as you can see is optional… keep this in mind)
• and a bunch of other stuff… like different system images for the Android emulator.

The second tab SDK Tools shows a bunch of other tools which are still part of the SDK, but platform version independent, which means they might be released or updated separately.

It stands for Application Programming Interface. It is simply an interface, an abstraction layer that allows communications between two different “pieces” of software. It works as a contract between the provider (e.g. a library) and the consumer (e.g. an app)
It is a set of formal definitions such as classes, methods, functions, modules, constants that can be used by other developers to write their code. Also, an API does not include implementation.

API Level

API Level is an integer value that uniquely identifies the framework API revision offered by a version of the Android platform.
Usually, updates to the framework API are designed so that the new API remains compatible with earlier versions of the API, for this reason, most of the changes to the new API are additive and the old parts of API are deprecated but not removed.

But now someone could argue…

if an Android API doesn’t provide implementation and the SDK Manager offers an optional downloadable API source code as part of the SDK, where is the actual implementation?

The answer is easy. On the device.

Let’s go through this quickly…

From source code to an APK file

Generally, an Android project is composed by the code developers write using Android API (the application module), plus some other libraries/dependencies (.jar, AAR, local modules…etc) and some resources.
The compilation process converts Java/Kotlin code, dependencies included (one reason to shrink your code!), into DEX byte-code and then compressed everything into an APK file along with some resources. At this stage, the implementation of the API is not included in the resulting APK!

DEX files and Android Runtime

The Android Runtime is where all the dirty job is done and where DEX files are executed. It is made of two main components:

• a Virtual Machine in order to take advantages of code portability and platform independence. Starting from Android 5.0 (Lollipop) the old runtime environment, Dalvik Virtual Machine, has been totally replaced by the new Android RunTime (ART). Dalvik used a JIT compiler, whereas ART uses AOT (Ahead of time) compilation plus JIT for runtime code profiling.
• Core Libraries are standard Java libraries and Android libraries. In simple words, this is where the implementation of the API resides.
  The API version available at this level is the one offered by the version of the Android platform in which the app is running.
  For example, if the actual device has installed Android 9 (Pie), all the APIs until API Level 28 are available.

If the few key concepts of how the Android Runtime works and what is the role of the API is clear so far, then it should be quite easy to understand backward/forward compatibility and the usage of compileSdkVersion, minSdkVersion and targetSdkVersion.

compileSdkVersion

This value is used only to tell Gradle what version of the SDK to compile your app with. For developers, it allows accessing to all the APIs available up to API Level set to compileSdkVersion.

It is strongly recommended to compile against the latest SDK version:

• a high API Level allows developers to take advantages of the latest APIs and capabilities provided by new platforms.
• in order to use the latest SupportLibrary, compileSdkVersion has to match the SupportLibrary version too.
  For example, in order to use SupportLibrary-28.x.x, compileSdkVersion has to be set to 28 as well.
• for migrating to/using AndroidX, compileSdkVersion has to be set at 28 at least.
• getting ready to satisfy Google Play’s target API level requirement. As announced by Google, in order to spread new Android versions quicker out in the market, every year Google will enforce a minimum target API Level for new applications and updates. More info here and here.

Android applications are forward-compatible with new versions of the Android platform because API changes are generally additive and old APIs might be deprecated, but not removed.
That means forward compatibility is basically guaranteed by the platform and running an application on a device with a higher API Level than the one specified in compileSdkVersion does not have any runtime issue, the application runs as expected on newer platform versions too.

App + compileSdkVersion = 26 and using an API xyz() introduced in API Level 26 can run on a device with Android 8 Oreo (API Level 26).
The same app can run on a device with Android 9 Pie (API Level 28) since the API xyz() is still available in API Level 28 .

minSdkVersion

This value specifies the minimum API Level in which the application is able to run. It’s the minimum requirement. If not specified, the default value is 1.

It is developers responsibility to set a proper value and ensure the application runs properly down to this API Level. This is called backward compatibility.
During development, Lint will also warn developers when trying to use any API above the specified minSdkVersion. It is really important to not ignore these warnings and fix them!
In order to provide backward compatibility, developers can check at runtime the platform version and use a new API on newer versions of the platform and old API on older versions or, depending on the case, using some static libraries which offer backward compatibility.

It is also important to mention Google Play Store uses this value to determinate if an app can be installed on a specific device by matching the device platform version with the app minSdkVersion.
Developers should be really careful when picking this value since backward compatibility is not guaranteed by the platform.
Picking a “right” value for a project is also a business decision since it affects how big is the audience the application is made for. Have a look at the platform distribution.

For example:
App + compileSdkVersion = 26 + minSdkVersion = 22 and using an API xyz() introduced in API Level 26 can run on a device with Android 8 Oreo (API Level 26).

The same app can be installed and run on an older device with Android 5.1 Lollipop (API Level 22), where the API xyz() does not exist. If no backward compatibility has been provided by developers either with runtime checks or some sort of libraries, then the application will crash as soon as it tries to access the API xyz().

targetSdkVersion

This value specifies the API Level on which the application is designed to run.
It doesn’t have to be confused with compileSdkVersion. The latter is only used at compile time and it makes new APIs available to developers. The former, instead, is part of the APK (as well as the minSdkVersion) and changes runtime behavior. It is the way developers can control forward compatibility.
Sometimes there might be some API changes on the underlying system that can affect how an application behaves when is running on a new runtime environment.
Targeting an application to a specific version enables all of those system runtime behaviors, which are dependent on that specific version of the platform. If an app is not ready to support these runtime behavior changes it is likely going to crash.
A simple example is the Runtime Permission, which has been introduced with Android 6 Marshmallow (API Level 23).
It is possible for an application to compile against API Level 23, but targeting API Level 22 if it is not ready yet to adopt the new runtime permission model.
In this way, an application can still be forward compatible without enabling the new runtime behavior.

Anyway, as already mentioned Google is enforcing apps to satisfy new target API level requirements, so it should be a high priority to always update this value.

Putting all together at the end there is a clear relationship

Keep in mind it is highly recommended to compile against the latest API Level and try to have targetSdkVersion == compileSdkVersion.

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