Choose a company that can say no to part of the brief. Ask who will decide the first release, who will design the journeys, and who will be there after the store approves the app. A portfolio of screens is not the same answer.
Ask how they choose native or cross-platform, and what they refuse to invent: prices, timelines, and results they have not measured. The reply should be specific to your job, not a package.
Sovassa starts with that conversation. If the problem is not one we should take, we say so before a proposal.