I don't think it's a community thing. I would absolutely use tests if I was writing any interesting, algorithmic code. Compilers, data structures, pathfinding, whatever. But most iOS apps are one half glue code that interacts with a JSON backend, and one half GUI code. Neither half is fun to test. And from my experience with coders who insist on tests, they never catch the interesting bugs anyway - session expiry in the wrong screen, animations that break if you interact with them too fast, using APIs that are not available on $(previous iOS), etc.