I’ve been using Maestro for two very large Flutter apps and it’s been so ahead of every other option is not even funny.

No long compilation times, no half baked testing dev experience, supports iOS and Android, no pumpAndSettle BS, No Flutter hacks, multiple cloud providers (cloud.mobile.dev, moropo), you can interact with native elements, so you can work with push notifications, system dialogs, system settings, email clients, web views, browsers, and a very simple test definition files that every capable QA engineer can maintain with very little supervision from developers (no need for dart expertise for writing tests).

I can only recommend it.