LookOut Mobile is one of the best and MUST have Apps, it's Free and scans all apps for Malware etc.
http://market.android.com/details?id...=search_result
More detail on what's included in Lookout Mobile Security Free:
SECURITY
* Block malware, spyware, and phishing apps
* Scan every app you download to ensure they’re safe
* Schedule daily or weekly security scans
* Receive automatic protection against the latest threats
* Prevent viruses from being transferred from your phone to your PC
FIND MY PHONE
* Find your lost or stolen phone by locating it on a Google map
* Activate a loud alarm to find your phone nearby, even if it is on silent
* Locate your phone by remotely enabling GPS, so you can find your phone even if GPS is turned off
* Log in to myLookout.com from any web browser to locate your phone
BACKUP & RESTORE
* Securely back up your contacts
* Restore data to an existing phone
* Access all your backed up data securely, online at myLookout.com
* Lookout is certified by TRUSTe so you can rest assured your privacy and your data is protected
... all these features are completely FREE
Recent Praise for Lookout Mobile Security:
* "Must-have app!" - CNET
* "5 out of 5 Stars!" - PCWorld, Top 100 Products
* Named one of the top 25 Hottest Mobile Companies