When testing my web app on the iPad, I can enable the debugging console of Safari Mobile and happily read my logging output. I can not find a way to do the same for a stand-alone app, meaning the web app was "added to the home screen" and the window.navigator.standalone flag says true, but there is no "Debug Console" banner at the top like there is inside Safari Mobile.
I have a bug that only happens in stand-alone mode and am almost ready to add a little debugging console to my web app, or worse, go to the dreaded alert debugging method.
So, SO, any awSOme ideas?
use http://www.iwebinspector.com - only for ios5 and up though..
for ios6 you can use safari6 and remote debugging http://moduscreate.com/enable-remote-web-inspector-in-ios-6/
if you are not on mac or want true remote debug, you can use jsconsole.com
来源：https://stackoverflow.com/questions/9071022/debugging-console-for-stand-alone-web-app-on-ios