For a HomeKit-only motion sensor, the Aqara P2 is as good as any motion sensor on the market. You can automate your lights. You can leverage it to save energy costs. It has a long-lasting battery.

Earlier this year, I decked out my townhouse with a handful of motion sensors. I went with the Aqara P1 ($25, Amazon) sensor because it's affordable, has a battery life that lasts up to five years ...