Default need help with applications.

i bought a sim free defy on amazon uk, but when i try to install some aplications like apn droid or apnportugal, to turn off 3g and data" its eating my money " the phone gives me this error allways SORRY! The application APNdroid (process com.google.code.android) has stopped unexpectedly. Please try again".
I try to reboot, take the battery off, nothing works .