5. The Night Sky
Fancy yourself as a stargazer? If so, then you really need The Night Sky. Priced at a mere 69p, iCandi's superb app is a no-brainer download for amateur astronomers everywhere. Point your iPhone towards the stars and the app uses the compass and GPS to identify and make sense of what exactly it is you have been staring at for all these years! If this doesn't impress your mates, they are dead inside.