The real-time vaping feature lets you raise wattage/voltage by pulling up on the joystick and lower wattage/voltage by pushing down. You can set a minimum and maximum range so that it only goes as high and low as you want it to. For example, I could set a profile at 8 watts and set the device threshold for 7 watts minimum and 10 watts maximum. Pressing the firing button gives me 8 watts. Pulling up on the joystick increases it up to 10. You can set the speed of how fast the wattage increases too and can stop pulling the joystick (while still pressing) to keep it at the wattage that tastes good to you.
I hope I explained that well, but fear I did a bad job. It's a pretty interesting feature that's hard to explain, and I'm still wondering how well it will be received. Janty equated it with smoking tobacco cigarettes; you have your normal drag, but sometimes takes short puffs or long, deep drags. So far, I think the company has done a good job mimicking that.