App Inventor Beta Preview Known Issues

This is a beta preview release of App Inventor. There are known minor bugs and glitches, and occasional failures in connecting to the phone or in getting projects to build. This version should be stable enough for personal or educational use, although it would be a good idea to maintain backup copies of important projects.

There are also a couple of specific issues to watch out for. We're working on these, but we didn't want to hold up this release to wait until they were fixed.

Known Issues List:

  • Unable to load large projects: This version of App Inventor cannot load projects as large as last year's Google version. If you are trying to transfer over a large project (e.g., large numbers of image or sound files, or very large individual files) you may see the error "Unable to load project". The problem may be worse on slow connections.
  • Manipulating blocks while switching screens: If you are working with a multiscreen app and you switch screens, do not move blocks with the mouse or click links in the Blocks Editor until the new screen is done loading. If you do so, the Blocks editor can become confused about which screen you are working on, and you can get errors, or even lose blocks. The same warning applies when you switch between projects. When loading a new project, don't use the Blocks editor until the project has finished loading.
  • Unstable project loading: We've gotten reports of projects loading incorrectly, with blocks missing. We're trying to track this down, but in the meantime be diligent about keeping local backups, especially for large and important projects.
  • Failure to package projects: We're currently seeing a 6% failure rate in attempts to package projects. Many of these appear to be intermittent. If your project fails to package, try again once or twice. Another source of failure may result from case collisions in the names of media files: If your project has two pictures named, for example, MyPict.jpg and mypict.jpg, this may cause errors.