I have a 2010 Fabia with the 1.6 diesel engine. A couple of years ago I bought an ODB2 reader (dongle). It worked fine for 30 minutes. Then it died. It was an ELM 327 and it cost about £15 so I wasn't too disappointed.

 

However, my Fabia has very little instrumentation. There is a blue light when the engine is cold, and, I guess (I've never seen it) a red light for when it is too hot. My son in law has a fancy £100 ODB2 reader which we tried on my car. It quickly spotted that the throttle pedal wasn't working as expected. It seemed that it was about 90% open when the car was idling. So that needed replacing. 

 

But if this gizmo could spot those sort of problems then I wanted one. I bought a Blue Driver dongle from Amazon (UK branch), plugged it in and after connecting it via Bluetooth to my computer tablet, I have a good range of information continuously.

 

One small problem. The dongle is made in the USA and works with cars there. This includes VW, Audi and Seat cars but not Skodas. I contacted the manufacturer who says they are looking into providing cover for Skodas as some are being sold there now.

 

Meanwhile, I have identified my car as a 2010 Seat and it works. The range of data available is somewhat restricted; no oil pressure or temperature. I am hoping that if Skodas are added or I experiment with the car brand (my Son in Law has a Mercedes) it should provide more readings. 

 

Meanwhile the dongle and an excellent app are doing good allowing me to read fault codes and reset them (after fixing the problem) as well as presenting a continuous display of coolant temperature, air inlet pressure and temperature, engine revs and engine speed.

 

This is the Blue Driver web site:-

https://www.bluedriver.com/home2?utm_expid=.yx6vB3NmRXul6yOPLFUViA.1&utm_referrer=https%3A%2F%2Fwww.google.co.uk%2F

 

For OBD2 standard code reading and live data you can expect most OBD2 devices to perform somewhat equally. Some (ie. more expensive ones) will be superior with regards to data logging and visualisation and whatnot, but they're generally the same. It's in the manufacturer specific stuff is where it gets a bit more annoying. I don't understand why you bought a reasonably expensive device that isn't specified to work with your car, and why you didn't go for something tailored for European cars or Skodas specifically.

OBD2 is a standard protocol, it's not specific to a brand, let alone VAG; although they overlay the soft options software (VCDS for example). I'm about to buy a dongle, what's a good make off ebay, less than a tenner?!