Xcode\'s debugger console makes it easy to see any debugging messages my app sends out using NSLog(), but it always sticks a timestamp prefix on them:
A way to keep using NSLog in conjunction with bbum's answer is to use a preprocessor macro to redefine NSLog to your own function
#define USECUSTOMLOGS 1
#if USECUSTOMLOGS
#define NSLog MyLog
#endif
This will replace NSLog with MyLog on compile time. Basically you can keep using NSLog everywhere and it will still use your custom format for the console window. You can also change it back to use NSLog at anytime by changing the 1 to a 0.