That's an integral part of how it works. Their sync servers download your email, then sync with your local client. You need that ID to log into their server and access your individual email accounts.
If you're on the Basic edition, your emails never touch our servers. This was a huge undertaking (it's not easy to port a sync-engine written in Python and designed to run on servers to run efficiently on desktop machines) and is the major reason why we can now offer a freemium service. We're going to put out a blog post soon with more engineering details soon!
Looking forward to it!
I think for this audience, this blog post raises more questions than it answers.
I'm a student, I can't justify $12pm (or $7pm) for an email client however good it is - but I'll gladly use the Basic version and continue contributing; pay a little back that way :)
https://www.dropbox.com/s/s37onyv41w91zi0/Screenshot%202017-...
Cloud now used for "much much much much less" [0] - just tracking and stuff. Sync-engine also (?) runs locally now, I'm not totally clear on how this works but there's apparently some currently closed source stuff to become open 'soon', so it should become clearer exactly what's going on.
There's also apparently some details to follow on their engineering blog [1].
[0] - https://github.com/nylas/N1/issues/3166 [1] - https://nylas.com/blog