Yes. Combine your approach with a new device, a mailbox size of several gigabytes and EDGE&#x2F;2G network connection.<p>IMAP&#x2F;JMAP will work fine in those conditions, as a client can simply fetch the list of folders and a few email headers, and then lazily fetch email bodies on demand. Updating the read status is pretty cheap and does not require a full sync between the device and server, and so on.