Huh? It does work well. It's just an ordinary raspberry pi. No modifications. I upgraded to using my pi 4 though. I just toss it in a workout armband along with a battery pack whenever I feel like it. Input device can be whatever you want. I usually use a bluetooth media remote since that's a keyboard with a trackpad that easily fits in my pocket. Real world battery life of almost 8 hours on a 10000mAh pack including the vufine plugged in at all times despite its internal battery.

Maybe the only thing I sort of had to hack together was the stupid mount for the vufine which is a bit cheap and flimsy. This is a necessary mod anyway if you buy one of these and want to use it for anything serious. I dremeled out a channel on the magnetic mount and ran a velcro zip tie through that. Holds onto a pair of glasses very firmly now. I added a second velcro strap around the body of it for stability. I can even go out for a jog no problems. All the cables I use are thin and lightweight (meant for connecting HDMI on a drone).

It's such a cheap and obvious idea that you can unregretfully drunk buy all the parts on amazon right now for probably less than I paid back then and you'd still just have a pile of otherwise useful stuff. The hunt for durable low-profile and L-angled cables needed to cram it all into a pocket is the expensive part, but you might even already have a pile of those.