Lookout does it for you.
We perform our own virus and malware analysis and push out updates to the virus-checking system on a regular basis. Lookout on your phone or tablet will check in with our servers and update as necessary with the current files to keep your devices protected. No need to worry if this doesn't occur on a precise schedule; think of it happening on an "as needed" basis.
Note: Click here for further information on what Lookout scans for.