I'm starting mobile development, and I would want to know if it's necessary to target a specific smartphone, or nowadays one can run a simulation that will provide accurate data of how the game will perform on a given device.
If simulation tools are not good enough, what version of iPhone and what Android mobile should I target as of 2013, for making games like Angry Birds, Jetpack Joyride, etc? (2D games only) I would buy that smartphone and make my tests there.
No simulators that I know of give reasonable expectations of on-device performance. The iOS simulator, in particular, is very bad. And I think the Android one is an emulator.
Yes, before starting Android game development, you must have a real phone, not emulator. Emulator in almost all cases doesn't work as expected and it can really make trouble.