I have an android (HTC Inspire), and use AVG's Mobilation app, which scans any new downloads before they are installed.
AVG Mobilation Free combats viruses and malware, and also provides loss and theft protection through the ability to track and control your smartphone remotely if you should become separated from it.
you can locate, lock, or wipe your phone with this app.
find a good app for backing up your data (Ti Backup) if your phone crashes(saves to micro sd card)
and a password protected storage app (Pocket) for your important data.