Email expiration dates
I want the ability to set an "expiration date" on an email, at which point it will be removed from the inbox and into my archive.
If I have an email about an event I'm attending, I want to keep that in my inbox as a reminder - but once that event is over, I have no need to keep it. If I could set an expiration date on it, I could let it automatically delete when I no longer need it.
I would love to see this implemented through Gmail labels with relative date handling available. That way I could create a filter that labels newsletters with "Expiration: 1 week", and have Boxer automatically remove them a week after the sent date.
Also, starring/flagging an email could represent an override, causing Boxer to ignore the expiration date. (This behavior could be a toggle in the Settings.)
adding expiration dates are what I too am looking for in an Android email app.