An emulator is software that imitates a device, such as a particular phone model and operating system version, on a computer. Mobile testers use emulators, and the closely related simulators, to run apps without owning every physical device.
Why it matters: Emulators are cheap and quick, so they're a good way to find functional bugs early and cover devices a team doesn't own. But they can't fully reproduce real hardware, so relying on them alone leaves gaps.
In practice: Teams start with emulators to find functional problems, then move to real devices, or cloud-hosted devices, for testing in real-world conditions. Real devices show how touch gestures, sensors, network changes, battery levels and performance actually behave.
Examples:
- Using emulators for early functional checks, then moving to real devices to test gestures and networks.
- Covering an older Android version on an emulator when no physical device is available.
Common pitfalls:
- Signing off mobile testing using emulators only.
- Testing accessibility on an emulator, where screen reader gestures don't behave as they do on a real phone.
Should you test mobile apps on emulators or real devices? Both. Emulators are fast and cheap for early functional testing. Real devices are needed to see how an app behaves with real hardware, networks and gestures.
