MySocialApp - Seamless Social Networking features for your app
AppyBuilder - An App Inventor 2 spin-off. Formerly called AILiveComplete.
Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
AppMySite - An automated no-code app builder
Manyverse - A social network off the grid
AppyPie AppMakr - AppMakr is a browser-based platform designed to make creating your own iPhone app quick and easy.