There's a new version of the app in active development. It will feature:
- An Action Bar UI that is compatible with all versions 1.6 and higher
- Streamlined interface to reduce required clicks from 2 to 1 if the same groups will be sent to
- Multiple groups selectable in 1 message
That's all I'm going to promise this far ;) There will almost certainly be more new features included. Stay tuned for details and screen shots as the release gets closer.