Comparing two devices

Compare puts two devices side by side while you use your app on both: an old Android next to a new one, a Pixel next to an iPhone, a phone next to a tablet.

Start a second emulator or simulator and it shows up in the against picker. The view then has:

• Both screens, refreshed every few seconds.
• CPU and memory charts for both at once, for the app picked in the toolbar when it runs on both (device-wide otherwise), so you can see which one works harder.
• Differences: every fact the two devices report (OS, build, hardware, display, battery, locale) lined up, with what differs highlighted. Tick Show what matches for the full list.

From a terminal:

emulabzip compare emulator-5554 "iPhone 17"          # only what differs
emulabzip compare emulator-5554 emulator-5556 --all  # everything
emulabzip compare emulator-5554 emulator-5556 --json

Facts one device does not have show as —. Comparing an Android device with an iOS one is allowed, though most rows will differ because the platforms name things differently.