Skiff (email service) – Wikipedia already mentioned them as too good to be true for a while:
It launched in 2021 and was developed in San Francisco, California. In November 2023, it reached its own record of almost 2 million users (17 months since launch).
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In a 2023 article, PCMAG reviewed Skiff pointing that Skiff offers “End-to-end encryption for email, collaboration, and calendar”, making complements to the fact of its services being free and easy to use (while being available as Apps for macOS, Android, and iOS).
This was all in the midst of me trying to find another place for our mail than GMail, and I am considering Proton Mail (which is profitable and offers both paid and free plans).
I had heard about Skiff Mail, and was lucky to not have included them on the shortlist as mid February, the above Wikipedia articled was updated to contain these two sections:
The Wiert Corner - irregular stream of stuff 