Iphone4 debugger

Is there any application debugger available in iphone sdk 4.0 ? I am build an ipod application . Its work well in ipod (Both simulator and device). But my friend having mo开发者_JS百科bile iphone4 , so i build the application and gave him as a app file.

He installed in his iphone4 via itunes it crashes many times . But the same application installed in my 1 st generation ipod its work well... How could i detect what mistakes i did in my application ?...

Can anyone help me ?

Thanks in advance... I tried lot but nothing got an good explanation.

(Note : Is there any debugger for detecting app crashes in iphone4 ? (only with app(release-iphoneos file))).

Your friend can send you the crash reports, which you can use to track down the problem.

Debugging is possible but needs the device connected to your computer.