Just had a fiddle with carista today on a 69 reg RS3 while I was hiding form the other half and the weekend chores.
Seems there is no stop-start disable possible on the newer cars, which was disappointing, but expected from what I'd read already. I'd be interested to know if OBDeleven will actually do it - they both advertise the ability.
The only things I can see (advertised) that OBDeleven does over what I did today with carista is that it can possibly enable video in motion, change how the DRLs stay on or off or dim with the turn signals and the door dinger. Everything else was possible on Carista (and for much much cheaper). OBDeleven obviously does long coding. but there doesn't seem too be a tonne of support yet.
What I did today:
Pulsing starter button
Deactivated DRL's when switched off to "0", and added the ability to turn them on or off in the MMI
Beep when locked by remote, and again added the on/off in the MMI
Changed sunroof opening from tilt to slide with the key fob
Seat belt warning off
Added an extra blink to the turn signal
Turned off the headlight washer
I'm curious about the throttle response changed to linear rather than by time, but not played with it yet, and also the Haldex RWD biasing, but thing I'll speak to a tuner before I enable them.
In all, a fun way to waste an hour, and a few customisations make the car your own a bit more than what Audi provided. For 12.99 on eBay it was money well spent