Wearable fitness apps report wildly inaccurate calorie burn and lose data on cross-platform sync

Wearable fitness trackers routinely over or under report calorie burn by 20 to 60 percent, with Samsung Galaxy Watch users reporting figures like 1700 calories burned while sedentary. Existing cross-platform apps aggregate data but never correct for device-specific error, leaving users unable to trust the numbers they base eating and training on. This app sits between the user's wearables and their health log, applying a per-device calibration layer built from the user's own baseline tests, then syncing the corrected figures across every connected device without data loss.