The $100 Nest Protect popularized the smart smoke detector, and the second generation model is still one of the best out there. Nest will send you an alert when it smells smoke or carbon monoxide, but you can also silence a false alarm with the app and integrate it to your larger smart home through IFTTT or other Nest devices like the Nest Thermostat or the Nest Cam.
If you want your smoke detector to do a little more when there isn't an emergency, the Onelink Safe & Sound offers the most creative combination of features of the bunch. As you'd expect, you'll get push alerts when your combination smoke and carbon monoxide alarm goes off, but the $250 Safe & Sound also has a built-in smart speaker complete with Amazon's assistant Alexa.
You can actually talk to your ceiling with this smoke alarm, and it'll respond by playing music, controlling your smart home or any of the other tasks that Alexa can do with a voice command.
Hopefully, the Safe & Sound is better than this dud -- which is also a smart smoke and CO alarm from First Alert. You will eventually get push alerts from the $120 Onelink by First Alert Wi-Fi Smoke + CO Alarm, but they take too long to arrive to be useful.
The alarm also works with Apple's digital assistant Siri, but the integration is useless. First Alert's first foray into smart smoke detectors has a bunch of cool sounding features but needs a lot more polish.
Netatmo's upcoming alarm will try to give Apple HomeKit a successful competitor to the Nest Protect. It has a lot of the same features as First Alert's Siri-enabled alarm, so hopefully those features will be better implemented on this upcoming device.
Unfortunately, one of the best competitors to the Nest Protect is no longer available. You can no longer buy the Halo+, as the company behind it folded, but the smart detector combined the normal push alerts with helpful weather notifications.
The customizable weather alerts allowed you to turn off your phone at night, knowing your smoke detector would let you know if there was a dangerous event such as a tornado in your area.
The Roost Smart Battery remains one of my favorite competitors to the Nest Protect, despite the fact that it's not really a smoke detector per se.
Instead, it's a $35 9V you can install into your existing detectors by simply replacing the battery. Roost's creative retrofit solution offers the same push notifications of full replacements for much less.
Another alternative to replacing your smoke detectors, the $100 Leeo plugs into your wall and acts as a color changing nightlight while listening for the sound of your alarms. You'll get a push notification when they sound, and if you place Leeo in a hallway, it can listen for alarms all across your home.