SourceForge
GitHub
GitLab
BitBucket
openDesktop.org
Gitea
Launchpad.net
OSOR
Amazon Appstore
F-Droid
Aptoide
GetJar
AppBrain
SlideME
AndroidPIT
APKMirror
SourceForge
Amazon AppstoreThe Amazon Appstore is recommended for users who frequently use Amazon services or devices, those looking for app deals and free offerings, and users who want an alternative app source aside from the dominant app stores.
GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.
F-Droid - F-Droid is an interesting alternative for Android users who want to try something different and not have to use the Goole Play store all the time.
GitLab - Create, review and deploy code together with GitLab open source git repo management software | GitLab
Aptoide - Aptoide is a third party replacement for the traditional Google Play Store.
BitBucket - Bitbucket is a free code hosting site for Mercurial and Git. Manage your development with a hosted wiki, issue tracker and source code.
GetJar - Discover and play paid apps and games for free.