Seems like 3rd party risk.
Discussion
there is none
But key is a multi-sig wallet solution, with TX only being signed and verified by 2/3 keys; one one the hardware, one on the app (locally), and one on the server
they can’t spend without one of the two that you hold
plus all code is open-source; as expected
nostr:note16gwmyrv2n068x0y2udyultzrrfkm7xnwqdwwve3xqrn7dly9a8mqy5wrh6