Hello, my name Vyacheslav, I'm from Russia (UTC+5)
I am expert android developer who works with GPS, GCM, Fragments, Multimedia, GreenDAO, JSON, REST, SQLite and so on.
I prefer to use git as a version control system (usually on bitbucket for closed-source projects, and github for open-source projects)
I can build backend part of solution for you. PHP and some database (mysql, postgresql or mongodb). But if you plan to use javascript web interface - you should additionally hire some frontend guy.
I think I have experience to manage your task in time.
You can take a look at my portfolio for examples of application which I have to build from the very start.
Please contact me and decribe your task in details