List of some app stores

1.Amazon app store 

it is initial release 22 march,2011 and was made available in nearly 200 countries.

supported os :- Android,FireOs,Blackbarry 10.

2.Getjar(older then playstore)

Founder :- Ilja Laurs

GetJar is an independent mobile phone app store founded in Lithuania in

2004, with offices in Vilnius, Lithuania and San Mateo, California.

Suported  os :-  Android,Symbian,Windows Mobile

3.Play store

It is a very famous app store.

It is created by Google.

Launched Date :- 22 October 2008

Platforms :- Android,chrome os.

4.Appbrain

Publisher: AppTornado

Platform: Android

5.F-Droid

Developer(s): Ciaran Gultnieks, F-Droid Limited.

Initial release date: 2010

Stable release: 1.7.1 (31 July 2019; 6 months ago).

Stable release: 1.7.1 (31 July 2019; 6 months ago).

 Android system (client), Linux, OSX, Windows 10, FreeBSD (server).

F-Droid is a community-maintained software repository for Android, similar to the Google Play store.

6.Apple app store

The App Store is a digital distribution platform, developed and maintained by Apple Inc., for mobile apps on its iOS operating system. it allows users to download and browse app which is developed by apple.

7.Apptoid

Aptoide is a software "marketplace" application for installing mobile applications which runs on the Android operating system.

written in :- JAVA

Source model: Open-source software

Initial release: November 17, 2009