Remember Google App Inventor, a Google Labs project that lets people without programming experience create Android apps for personal use? It is an interesting project, but so far, it has only been available as a private beta, which meant you needed an invitation to get in. According to the App Inventor team, their experiment has generated more interest than they had ever hoped for, with people creating apps ranging from vocabularies and SMS to marriage proposals.
To unlock the full potential, Google is now opening up App Inventor to anyone with a Google account - just head over to the App Inventor home page and sign up.
One thing to note though - apparently, when Google says "personal use," they actually mean it, and apps created with App Inventor cannot yet be published to the Market. The FAQ entry for the issue does say that they are working to resolve the technical issues behind this limitation, but as of right now, your creation will have to find other exposure channels.
Source: Google For Students