Comparing the free versions for Android and iPhone...

iPhone generally has a more accurate interpretation of where you tap the screen, so this makes the iPhone interface of the app a bit better (typing on the two devices would receive the same review from me).  However, the Android free version gives more information.  While the iPhone app gives only n-number, the Android free version gives n-number AND flight number.  I tried to cross-reference a few flights clicked at random from each device.  I would say about 75% accuracy (assuming flightaware is the end-all, tell-all for flight location).  I searched only by n-numbers when checking info on flightaware.  Some of them came up and said there was no record.  One came up and said the flight had landed 3 years ago.  But, not all planes are on flightaware, so that could easily explain that.  And the majority of flights obtained from either device were found on flightaware in the exact same location as shown on the devices.

From my understanding of the pay version, it works like Google Sky Map where you just point the phone.  The free version simply has a map and works like a portable flightaware.  My first thought was, "why not just use the data plan to browse flightaware" but then quickly realized that this app was much faster than browsing the internet and it gives you just enough info so that you can look it up more exhaustively later when processing pictures.

Do I have a preference between the two?  Well...the iPhone is slippery and I tend to drop it.  I'm not sure how relevant that is to reviewing this app...