Why do people use these (watches, bands, smart scales) when they are so inaccurate? It's like believing in astrology!

I am convinced people go into the market with money and a desire to get scammed and never bother to check any claims companies make about their products.

Other than tracking steps and heart rate, they aren't accurate for the other things they claim to do.

I can't believe people are using these devices and believing they are accurate.

If you want an accurate body fat percentage measurement, get a DXA scan.

Good BIA devices from InBody that are anywhere near as accurate as DXA (still far off) cost thousands of dollars.

For impedance based machines, look up InBody 970/970S and how much they cost!

Believing your Withings smart scale is accurate at all for body fat percentage measurement is like believing in a unicorn.

And for body weight measurement, you can use any cheap Chinese scale, take a photo, and most agents can read the readings off the photo and log it for you in any app, no Health Connect or HealthKit needed!

how much precision you even need for bodyweight? Chinese cheap scales are good enough and mass produced, dirt cheap. Also, your bodyweight does can vary by as much as 1.2kg or 1% of BW on day to day basis simply due to changes in hydration, gut content or hormonal effects etc... You'll need to use a "weight trend" method something like EMA-14 or SMA-7 which many fitness apps use.

We use KTS-3 (Kalman Trend Smoother) in macrocodex free app for weight trend, it's slightly better than EMA-14 but visually it's much better for the users specially the ones who aren't good at reading a chart!

OK, so you want other apps to read this data? Read on.

How much effort is needed to write an app that can take a photo, read the display, and write it to Health Connect or HealthKit? Barely a few minutes!

The same is true for a blood pressure monitor. How often do you even use it? How much effort?

Do you really even need an API? LOL.

You can find a few studies on this:

>A 2020 systematic review by Fuller et al. found that consumer wearables often perform poorly at estimating energy expenditure, even when they measure steps and heart rate reasonably well. Across brands like Apple, Garmin, Polar, and Withings, calorie burn estimates frequently showed substantial error, often in the 15–40% range and sometimes exceeding 50%. Wearables can still be useful for tracking trends, but not for precise calorie calculations.

And at the end, if you are interested in "Calorie Expenditure" or TDEE or Maintenance Calorie tracking, our sensorless approach is much more accurate and we've a completely free app with 17,000+ users already! We basically use a Neural Network, see the method here: https://macrocodex.app/knowledge/rethink/adaptive-tdee/

You can read reviews, and we guarantee results for weight loss or weight gain within 2–3 weeks (validation based on 17,000+ users), with no money, no ads served, and not even a name, phone number, or email (on Android) collected! Every user is just a number; no personally identifying information is collected.

It doesn't matter if a person has PCOD, thyroid issues, prediabetes, or is genetically resistant to fat loss: results within guaranteed 2–3 weeks and 80% will see results from the very first week! If you think our claim is outrageous, read the reviews :)

Don't trust? just read the reviews!

I convinced myself that it was for health but in practice mostly it’s for the following

0. Can see time in dark

1. Notifications, don’t have to take out the phone and doomscroll

2. Find my phone

3. Phone calls when my hands are busy and I stay away from my phone as much as possible

4. TickTick (notifications only, the app sucks on watch, use todoist if you want to USE it)

5. Timers, I follow pomodoro