I'm a vi user, and the inability to remap something to esc is grindingly frustrating. On the road i use 'jj' and at the office I have a variety of nice keyboard

I'm a vi user, and the inability to remap something to esc is grindingly frustrating. On the road i use 'jj' and at the office I have a variety of nice keyboards. Seems like there's a niche app for keyboard remapping. I'm not sure if that would be possible unjailbroken or not.