ActivityTracker can read motion data from both your iPhone and your Apple Watch.
In case you take steps with your Apple Watch alone you need to activate the syncing between your iPhone and your Watch in order to have the steps showing in ActivityTracker. To activate the sync go to Settings > Sync Watch & HealthKit.
If you take steps with your Apple Watch and without your iPhone you will not see the steps taken with your Watch unless you activate syncing from Settings > Sync Watch & HealthKit.
ActivityTracker reads the motion data from the motion processor in your iPhone or Apple Watch. It's the same data displayed by the Apple Health app. According to various tests the motion processor is very accurate, as accurate as a dedicated tracker like FitBit, Jawbone, you name it.
We take your privacy very seriously. We do not share or sell information about our customers. Ever. Our business model is to make money from upgrades to the Pro version only.
More so, all your motion data is stored in the app on your iPhone and nothing is sent to our servers. If you delete the app you delete all motion data gathered by ActivityTracker.
ActivityTracker reads the steps and flights of stairs climbed from the motion processor in your iPhone. The motion processor stores data for the last 7 days so we can get this historical data at first launch.
ActivityTracker uses scientific formulas to calculate those variables as accurately as possible. The distance is calculated from the steps you took and by taking into account your height and your sex. The burned calories are calculated from your steps and by taking into account your Weight, Height and Sex.
If you want to delete all your data from ActivityTracker you can just delete the app from your iPhone. Then install the app again to start fresh and even import your historical data again from HealthKit.
After downloading ActivityTracker on your iPhone you need to open the Watch app then select My Watch and scroll down until you find ActivityTracker. Then enable Show App on Apple Watch.
It can happen if the app data gets corrupted somehow (for example by importing a custom XML with bad formatting). The solution is to delete the app from your iPhone and then reinstall it. Since the historical data can be imported from Apple Health no data should be lost.
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