App Inventor Logo
http://ai2.appinventor.mit.edu/

But Wait, There's More

Once you understand how App Inventor works, how to access components and how to explore the component capabilities, then you can get serious

...did you notice the HELP? It does

help

Notice the little question marks (?) - clicking them gets a brief help, clicking on the contained link gives you more - often suggestions and code examples - neat.

interface

The main Interface palette contains most common controls.

 

layout The layout palette is important - you must use layouts to arrange components in particular places
drawing Graphics and game controls live in the Drawing and Animation palette
sensors The sensors palette gives you access to the phone's built in arrays, including accelerometer and clock
media The phone capacity can also be accessed via the Media palette, with camera and on-board media services
social Phone and social media apis can also be accessed via the Social Palette
storage Storage lets you use a number of cool methods of making persistent records. Tiny DBs live on the phone as do files. Tiny Web DBs and Fusion tables live in the cloud - all let you keep information so that subsequent runs of your app do not start blank.
connect Bluetooth connectivty is also possible
lego Control of Lego gear vua bluetooth is also fairly straight forward