It's only marginally related to the topic at hand as it isn't "HD" but this ones just for fun when filming with iPhones etc. Say you have a clip on fisheye ie the one I'm using which is:
First thing you'll encounter with shit like that is the vignette bouncing, to remedy that you can get the App procam 6 which is like £5 on the app store or free via Tweakbox if you're a cheap bastard like me. Now you've got that and disabled stabilization shit will be something like this (shrunk it down to fit slap but it was 1080p):
Procam has a funky lil feature that lets you select quality ranging from 480p to 4k and with 480p being 4:3 you can end up with something like this.
Bit heavy on the vig side but can easily zoom in a tad and fuck around with it. Not perfect nor is it HD 4:3 but I thought it was worth mentioning.