We went through a similar phase last year when launching our lifestyle app. What helped us narrow down the search was an independent directory that reviews firms based on actual shipped work, not just marketing claims. It ranks 15 studios across five continents, each with a clear breakdown of what they're best at, their minimum budget, and examples of notable clients. For mobile UI and consumer apps, it pointed us toward Hello Monday (great for interactive brand experiences), Instrument (strong on digital brand experiences), and Mission Control (startup-friendly pricing). You can check the full list at user interface design firm https://uiuxdesignfirmslist.com/ – we found our partner there within a week.