The Eufy C20 , which is also quite affordable, connects to your iPhone and the Apple Health.
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The scale works completely independently of any other electronic device or service. Integration with iPhone Apple Health is an optional extra, but not required, and there are no subscriptions or other upgrades.
The Eufy C20 has a relatively small footprint, measuring under 27cm, so you can place it in your bathroom without it taking up too much space. But the nice thing is that on top of the scale, there's a fairly large and bright 3.3-inch color display.
When you step on the scale, it will take your weight and take other measurements like body fat percentage and muscle mass at the same time. These numbers are easily visible on the large screen, and it will show you a small graph that shows the change over time compared to your last reading. Eufy says the scale is accurate to within about 50g (0.1lbs).
Optionally, you can enable heart rate monitoring as well, but this requires you to stand on the scale for a few extra seconds each time you want to take a reading.
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To add all of these stats to Apple Health, you connect the scale using the Eufy Life. It uses Bluetooth to communicate. The key thing is that the data is only sent to your iPhone when the Eufy app is open and you turn on the scale by tapping on it. So to sync your measurements to the Health app, the next time you step on the scale, just take your iPhone with you and open the Eufy app nearby.
Almost immediately, it will connect to the scale and your weight will be recorded within the Eufy Life, which then also sends it to the Apple Health database. You don't have to press any buttons, just have the app open, so it's pretty painless. A Bluetooth symbol appears on the scale's screen to confirm it's connected.
The Eufy Life app interface certainly isn't the best-designed app you've ever seen, but that doesn't matter. You don't have to use it. You just open it to connect to the scale, and then you can close it again and check your data in Health or any third-party app that communicates with the HealthKit.
You also don't have to remember to bring your phone every time you go to the bathroom to weigh yourself. The scale has a built-in memory and keeps track of your measurements from the past few weeks. If you step on the scale without your phone connected, it simply shows the information on its screen and saves it for later. The next time you stand with your iPhone present, it will sync your full measurement history.
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The only other thing you need to know about is multi-user support. If you have multiple members in your family, you can add each person as a separate profile on the scale to track their measurements independently, up to 16 users. These are properly rendered in the Eufy Life app, but there's no good way to sync each profile's data to each person's phone for storage in Apple Health. While there are some workarounds, the integration with Health is clearly designed for single-user operation.
