Ranked in these QuestionsQuestion Ranking
Pro Beautiful UI
Pro Open Source
Pro Has introduced features that are not available in better-known apps
Like a 'new generation' app - quite a revelation in simple addition of various emails from separate providers with different forms of password/2-step/other verification and sign ins - all failed by many better known apps on this list.
Con E-mail is synced in their own servers
aha - but Nylas is no longer N1 since January 2017.
This no longer applies!
Con High memory usage
Hige CPU and GPU usage for a mail client. Some computers may struggle and be slowed down by it.
Con Weak support
Bug fixes take too long to be released.
Con Custom IMAP accounts can not sync
Con High CPU usage
Con No more free version
Now 'Basic' is free. Basic is very good.
'Pro' is overkill for most users.