I&#x27;m also a big fan of IMAP and would <i>love</i> to see everyone keep to it. At the moment I haven&#x27;t found an IMAP client better than trojita (<a href="http:&#x2F;&#x2F;trojita.flaska.net&#x2F;" rel="nofollow">http:&#x2F;&#x2F;trojita.flaska.net&#x2F;</a>) which actually uses IMAP the way it was designed to and not as a poor man&#x27;s sync mechanism.<p>However, there are things that IMAP can&#x27;t do:<p>* Search has to be mailbox by mailbox. So if you have a huge number of mailboxes it&#x27;s going to take a long time. There is, of course, an extension for multi-mailbox search, but its very low adoption hasn&#x27;t made the thing practical<p>* Read notification just can&#x27;t be done with the traditional email system, short of replying with a specifically-formatted email and introducing some kind of RPC<p>* Send Later while offline can&#x27;t be done with the traditional email system. There&#x27;s just nothing you can do for that.