Do I need a developer, a designer, or both? — answered by Engineer Saeed Baatiah
If you already have a visual identity and only need it implemented, a developer with solid execution-level design sense is enough. If you are starting from zero with no logo, no palette, and no screen structure, you need a design phase first — otherwise you pay twice: once to build and once to rebuild after you see the result. Many independent developers cover both stages, which saves coordination time and rework cost.