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.
Helium - Helium lets you accept payments by credit card for anything you want to sell online.
APK Pure - Download apk for Android with APKPure APK downloader. NoAds, Faster apk downloads and apk file update speed. Best of all, it's free
PiP for Mac - Always on top window preview similar to the popular windows only OnTopReplica
APKMirror - Android Market and APK Downloads
PiPifier - PiPifier is a macOS 10.