Build a device-neutral relay that imports measurements from supported vendor accounts and phone health stores, reconciles duplicates and profile conflicts, and confirms that each reading reached its destination. It should preserve an independent backup and generate date-filtered weight or blood-pressure reports for clinicians. Start with a narrow compatibility set and a guided recovery service so difficult account, permission, and device-migration cases can be resolved manually.

Consumers increasingly combine hardware from several vendors while relying on Apple Health or Google Health Connect as the hub. Frequent app changes, subscription restrictions, and removed export features make an independent continuity layer more valuable, although platform access limits must be validated before building.