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My friend and I started a startup. I don't have any equity in the company since he is the one who set it all up. Currently we are only two people; we are looking to hire more. I'm working on the mobile app based on the idea (UI and back end).
How can I determine what my official title should be? Should I be calling myself just Android Developer? Or Software Engineer (Android)? Or CTO? Management or a developer or both.