Notion Mail Alternative With a Unified Inbox for Gmail, iCloud and Any IMAP Mailbox

Notion Mail was a good idea executed with taste. It brought the Notion way of thinking to an inbox: views you could define instead of folders you had to maintain, AI labels that learned from how you actually sorted, snippets for the replies you send twenty times a month, availability from Notion Calendar dropped straight into a message, and the ability to @mention a Notion page in a draft so the context traveled with the mail. For someone whose work already lived in Notion, that last part was the whole pitch. Notion retired it anyway, and the stated reason is worth reading carefully: the company said more than half of Notion Mail users were managing email without ever opening the inbox, so it put its effort into agents that act on mail rather than a client you sit in front of. Whatever you think of that bet, it left a concrete problem on a lot of desks. The deeper lesson is the one worth taking to whatever you choose next. Notion Mail was built on the Gmail API, which is what made the one-click setup and the tight Google Calendar work possible, and it is also why the product could never reach a mailbox Google does not run. A client welded to one provider inherits the boundaries of that provider and the roadmap of that vendor at the same time. Inboxes takes the opposite bet and sits on IMAP, an open standard every serious mail host has spoken for thirty years. Add a Gmail account with an app password, add the info@ address on your own domain with its IMAP host, add the iCloud account, and they land on the same board. AI reads every message as it arrives, assigns a category, decides whether it is spam regardless of what the provider filter waved through, and drafts a reply for anything it marks Important, with an undo window so nothing leaves without you clicking send.