Android Application Restriction

Is there any way to install some kind of policy/certificate that will restrict applications. Such as only allow application signed by google or not allowin开发者_运维知识库g any applications that require gps?

Only if you make custom firmware and probably a lot of modifications to the OS.

This isn't really the place for the questions, but I'll give you the answer. Google don't sign any applications. All you can do really is set it to only install market apps. Beyond that, it's just a case of not installing any apps that ask for permissions you don't want to give out, like fine or coarse GPS.