Thanks for Your replies! Looks like as of today, the Iphone has the better selection of apps for private pilots. Would be cool to have Air Nav Pro for Android. I recently stumbled upon the Samsung Galaxy 7'' tablet with Android 2.2. Could be a good compromise between a phone and a pad/Notebook.
Is the quality of the GPS on all devices equal / good enough, stable etc? Or did You encounter any GPS problems during flight?