I tried the PC sound card line-in, software based, poor man's oscilloscope but it doesn't give me the resolution I need and the levels are just a guess.
I can buy you beer, candy, pizza, make you parts on my CNC Mill, send you funny pictures, whatever. Currency, too!
My son has an iphone. Its sound quality is awful and its proximity detector or its touch screen keeps putting it on hold when he talks.
Its millions of features are simply cheap toys. But it is a pretty good camera and video playback device.