||The ECU will monitor and react to AFR much faster than us mere humans can. To answer your question if you want to see it - I was going to try and find one of the radio pocket gauge cluster bezels, but I don't think they're readily available.
I don't know how the data would be sent to a tablet or radio display, but that's pretty slick if you know how that works. For dialing in injectors, I just have been using the laptop, Fast and the Furious-like. But again, that's temporary. Once set up, it can do all the work itself without me needing to watch.