I happen to fall into the iPhone camp so I can't attest to the usability of Frodo C64, but it is a Commodore 64 emulator created for the Google Android mobile phone, netbook (and soon to be tablet) operating system. Androinica.com recently covered the application and their take-away was it's a little rough around the edges, and could be faster, particularly when it comes to games. The real trick though, is for someone within the GEOS community to get GEOS for Commodore up and running on the thing. Let us know if you were successful!

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Grab all the 8-bit Computer Nostalgia You Can Handle with Frodo C64