I'd like to 'tip' someone or simply give him some sats - and onboard to Alby - via e-mail.

Ie. I could just ask friend/waitress for an e-mail, input in my account (or send e-mail with a special URL), then she receives an invitation to join Alby where wallet with X sats is waiting for her.

Or if this person already has an account, Alby discovers their wallet associated with this e-mail and I send them sats.