Platforms

Phone and tablet

The iOS simulator is the one most people come for, and the reason is usually the Mac. Running an iPhone simulator locally needs macOS underneath it; running one in a browser tab does not, so a Windows or Linux machine can drive an iPhone or iPad without a Mac on the desk.

The Android emulator solves a different problem. Android tooling runs anywhere, so the constraint is not the operating system — it is that an emulator on your laptop is reachable only by you. A device that is a URL can be opened by a colleague, a designer, or a support agent.

Television

TV platforms differ from phones in one way that changes everything about testing them: there is no touch. Navigation is a d-pad moving focus between elements, so a test has to reason about what is focused rather than where to tap.

Apple TV and Android TV both run as cloud simulators with real d-pad control and focus-aware tests. If you ship a phone app and a TV app from the same codebase, the Android TV page covers driving both from the same APK.

Roku is the exception and the page says so up front. Roku publishes no emulator, so this is real hardware being streamed, and it is in beta: you can drive the remote and inspect the UI, but app upload and the test runner are not there yet. Read that page before planning around it.

What a simulator will not tell you

Worth being direct about, since every page here except Roku is a simulator or emulator. Some classes of bug only appear on physical hardware — anything involving the camera, real battery behaviour, cellular radios or thermal throttling. That set is shorter and more specific than the argument usually suggests, and knowing exactly what is in it is what lets you run most of a test suite on simulators honestly. Simulator vs real device goes through it properly.