I can not suggest as Mail providor
It seams not to be possible to unsubscribe from newsletter - I do it each single time and ask also support team to stop sending updates informations. After months change nothing. I close the skiff.com account.
Also I was not happy - there was no IMAP function - Means it was not possible to use Skiff with the default Apple Mail Client.
Also I think Skiff have no focus - it try to be Notion, Dropbox all in one - but it seams not to work, sometime is less more..

