PiP for Mac - Always on top window preview similar to the popular windows only OnTopReplica
GetStream.io - APIs for the development of scalable newsfeeds and chat applications.
Helium - Helium lets you accept payments by credit card for anything you want to sell online.
Declutter - Cleans and organises your files in Mac desktop automatically
X-Mouse Button Control - XMouse Button Control (XMBC) allows you to create application and window specific profiles.
ZmURL - Build a beautiful page for your Zoom event in 2 minutes