What are the alternatives ? MS band ? Apple watch ? xiaomi ?
Though they are still gathering a lot of data. It feels better than Fitbit/Google, but I wish they'd spend some time on encryption / privacy.
For example, all the GPS data, that's useful for showing a map of the run and measure the distance, but certainly doesn't need to go on their servers. They should encrypt the GPS points and only send the shape (vector path) to their servers. That would contain info about distance, but not where in the world the person was running.
Similar things could be done for other things.