How To Make Objects Appear Lit Without Using Lighting

I have a prefab, and i want to make the prefab (or just the visible mesh) appear lit, but i want to avoid using lights (due to performance on mobile devices).

Is their a setting, modeling convention, or import setting to allow objects to seem fully lit (like gui items or etc)?

Use an Unlit shader.

Which option do i select for the texture (or material) properties that is optimized for mobile? do i HAVE to use the mobile/transparent option to achieve transparency, or will unlit shader still have transparency?