Usable on Windows, Android and Ubuntu-Linux, with about the same core functionality.
Able to sync it's settings (and actions) between the two platform.
"Snooze" emails, or attach a timed notification to them.
Works with Gmail and IMAP4 or POP3.
Relatively good-looking interface is a bonus!
The most known clients I know of (Thunderbird, Opera Mail, Outlook, etc.) all fail at the cross-platform requirement. Do you know any with these features?
If not, Windows+Android or Linux+Android ones are also in my interest.
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