Why your wearable data differs between apps

What causes the differences?

• Different sources: phone sensors versus a wrist or ring device.
• Different methods: sleep staging and HRV algorithms vary.
• Different windows: “today” may be midnight to midnight or wake to wake.
• Sync lag: one app may not have received the latest data.
• Deduplication: overlapping sources can double count unless handled carefully.

Why is missing data different from zero?

If a device was off, the right answer is “no data”, not 0 steps or 0 hours of sleep. Treating gaps as zero drags averages and scores down and tells a false story. A trustworthy app shows gaps and says how much real data supports each number.

How do you make sense of it?

1. Choose a primary source per metric and stay with it.
2. Check the last-synced time.
3. Compare your weekly average, not a single day.
4. Look for apps that show the source and time of each reading. See how Health Connect shares data.

What does this look like in practice?

Imagine a phone in your pocket and a watch on your wrist. The phone logs 6,200 steps, the watch 7,100, and a third app shows 7,400 because it combined both. None is lying; each answers a slightly different question. If you pick the watch as your source and stay with it, your trend stays meaningful even if the absolute number never matches anyone else’s.

What are simple rules for trusting your data?

1. One primary source per metric.
2. Trends over single days.
3. Gaps are gaps, not zeros.
4. Changes of device or app are breaks in the series; expect a step change.

Where does Bodhara fit?

This is the problem Bodhara is built around: provenance, units and retrieval time are kept with each record. Bodhara is being designed as an Android-first, local-first app: your health records stay on your phone, every number shows where it came from, and missing data is shown as missing rather than as zero. It is in development, so specific device support and launch timing are not final. We will publish verified details before calling any connection supported.

Frequently asked questions

Why do my steps differ between my phone and watch?

They are separate sensors with different placement and algorithms, and an app may combine or choose between them.

Which source should I trust?

Pick one primary source per metric and judge it by consistency over time.

Is a missing night the same as a bad night?

No. Missing means no measurement. A good app shows it as a gap.