This is pretty cool and I would encourage everyone to check it out. Be sure to create an account at VirusTotal so you can submit unknown apps to the scanner and make everyones device using the VirusTotal app safer.
VirusTotal for Android checks the applications installed in your Android phone against VirusTotal (http://www.virustotal.com).
It will inform you about malware (virus, trojans, worms) on your phone and allows you to upload any unknown applications to VirusTotal. In other words, VirusTotal for Android will get your applications scanned by more than 40 antivirus, flagging any undesired content.
Please note that VirusTotal for Android does not provide real-time protection and, so, is no substitute for any antivirus product, just a second opinion regarding your apps.