I don't want to setp on any VCDS toes but am just going to list my experiences with OBD stuff a bit ...

To start ...

I have been impressed with this forum and the level of knowledge and also the different approach to tuning, diagnostics and maintenance of the VAG cars given the OBD features in the ME Motronic 7.5 ECU.

I bought my S3 recently and so wanted to explore its tuning potential, understand it under the skin a bit and diagnose its laggy power delivery with the GTRS turbo it has. After doing loads of research and on this forum and others about the engine and control systems and playing around with things like the N75, N249, MBC etc. I settled with the configuration of N75 and N249 connected and MBC removed. This was without doing any logging and using just a boost gauge, my gut feel and OBD handheld scan tool that I had.

I had become intrigued by it all so decided to explore some options further, partly because I am a gadget and car tuning geek - my professional background being originally software engineering and now software development and systems integration ...

Outside of the VAGCOM and VCDS (I have the 409-1 software on my laptop) which is well covered on here anyway I started looking at in-car options and other software - and this is just to further satisfy my own curiosity for such things ...

To date I have accumulated and am experimenting with ...

My old Geniscan GS400 hand-held scanner - for simple code reading and re-setting GENISCAN GS400---YOHO Technology Co.,Ltd
An OBD USB FTDI cable - for use with a USB Laptop port Amazon.co.uk: obd cable
An OBD ELM327 Mini Bluetooth adaptor - for use with Bluetooth enabled devices Amazon.co.uk: elm327 mini
Torque Pro Android App with the Torque Scan plugin - to explore some of the simpler OBD capabilities Torque — OBD2 Performance and Diagnostics for your Vehicle

I am also considering the ...

Dashcommand i-pad App - for easier experimentation and just to have a play about really DashCommand - Palmer Performance Engineering, Inc.
OBD Facile software - they have great reference data on their site Outils OBD Facile - Information on OBD and diagnostic interfaces ELM327
... and a few other bits of software

That's it for now ... so time for some more experimentation over the weekend ...

Martin