Thank you for the various replies. I note in particular the comment regarding different operating systems for phones and desk tops/laptops.
I have Pscan on my Windows laptop which is great.
I have downloaded an app called Rovermems ( https://rovermems.com/ ) that operates on android phones (not windows/Mac/Linux). I am awaiting for the lead to connect from my phone to the OBDS connection to try it out. On the 2J mems, it only appears to read 5 or so sensor outputs (on the 1.6 and 1.9 MEMS, many more sensors are read).
For MEMS 1.6 / 1.9 ECU the android solution is here - https://memsdiag.blogspot.com/ and looks even more comprehensive.