This year's Android Developer Challenge showed off an enormous variety of complex applications that let users play guitar, learn about astronomy, get information on famous art or even chase down ghosts. We've picked out the 12 coolest apps.
SongDNA is a sort of encyclopedia for songs, where users enter the title of their favourite songs and get a plethora of information about it, including an artist bio, song lyrics, its chart rankings and even a link to its music video.
This app, which is currently for sale on the Apple iPhone App Store, is not yet available on the Android Market.
Developer: Coding Caveman
Price: $1.50 (91p)
If you've always wanted to learn to play guitar but have been either too lazy or untalented to do so, then Solo is an app made specifically for you!
Solo cleverly uses the touchscreen to create a series of virtual guitar strings that can be either plucked or strummed to more or less recreate the sensation of playing an actual instrument.
Users can program different chords into the app to get different notes and the app even shows you how to play the chords on an actual guitar should you choose to do so.
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