The only thing that matter to me is can it run a terminal and can it run emacs. With the ipad/iphone failing on both those, this is quite forward to me
I’m not advocating that you _should_ do this, but you definitely _could_ do _at least_:
Install an ssh app (they exist for iOS. I’ve used them. They’re ok! They’d be better w a paired Bluetooth keyboard, easy to come by)
Log into your server of choice—even just your personal machine on your LAN
Hack away in emacs
This has the added benefit of not requiring local access to files on your mobile device, or setting up yet another custom dev environment on a new system
