Good idea in general, the term for this category of products is personal information management system (PIMS). digi.me is the largest player but even they can't

Good idea in general, the term for this category of products is personal information management system (PIMS). digi.me is the largest player but even they can't seem to get any reasonable traction, as it's an uphill battle to convince third parties to integrate with you. Classical chicken & egg problem: If you have many users the integrations will come naturally, but users will only come when there are enough integrations. A large company like Apple would be in a better position to do something like this, and in principle Apple Pay does it already as merchants can e.g. request your shipping or billing address through that system.