Ability to send my email at a later specified time.
Jamie Kahn Genet commented
Yeah, that is a handy feature I find myself switching to webmail just to access. I would worry if it were not handled server-side, though. I'd hate to be out of 'net coverage or have iOS fail to keep Airmail running in the background to have the email send exactly when desired.
How is this kind of thing usually handled? *curious*