So... Like alby but it's own app?
Discussion
More or less, yep!
Amber implements NIP-46. It stores your nsec and signs notes on behalf of your npub without ever revealing your nsec to the client.
It can fully replace local app storage of nsecs as well as NIP-07 browser extensions (like Alby) for apps that support remote signing.
Just tacking on to that, web apps don't seem to work often or at all. I think they just need time to get it implemented. Ncryptsec can be generated, though. Things like npub.cash can be signed in that way.
I've used Amber to sign in to noStrudel, though I still use Alby for most browser apps.