Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
Sencha Touch - The leading mobile web app framework based on HTML5 for amazing mobile apps.
AppsGeyser - Appsgeyser is the easiest to use DIY native mobile app creation platform.
Appcelerator Titanium - Appcelerator Open Source
MySocialApp - Seamless Social Networking features for your app
MyEclipse - Hybrid mobile app technology is the wave of the future.