Obtainium allows you to install and update Apps directly from their releases pages, and receive notifications when new releases are made available.

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Currently supported App sources:

Open Source - General:

GitHub
GitLab
Codeberg
F-Droid
Third Party F-Droid Repos
IzzyOnDroid
SourceForge
SourceHut
Other - General:

APKPure
Aptoide
Uptodowng
APKMirror (Track-Only)
Huawei AppGallery
Jenkins Jobs
Open Source - App-Specific:

Mullvad
Signal
VLC
Other - App-Specific:

WhatsApp
Telegram