No more crime and we dont even need Batman or the Avengers

Everyone now has a cell phone. When a crime goes down, be it a bank robbery or 7-11 hold up. The proprietor should be able to alert the police and they should be able to run a trace via ATT, TMobile etc to see who was in the area at the time. Based on that and eye witnesses they can nab the perpetrator. Even better if its a modern smart phone, maybe the smart phone can be made to "alert" the sore to its presence and then you can trace it the owner and arrest them.