The real Cheapee's can be a bit hit and miss, in fact you dont really know what your buying these days whether cheap or not they all seam to be Clones of clones of clones, the original Long Grey ELM27 are the best ( see pic below) but again theve been cloned up so many times its a punt.
The really cheap ones all seem to work, for a while, then suffer intermittent connection issues, Hang with an App or just die, my guess is through poor workmanship or dry joints or crappy components,
I bought a few of those Baby Blue Mini ones a while back, think I picked them up for around 80p a hit, down to a few now that I haven't lost, left in cars or just died.
The last one I bought was a Viecar, which appeared to look and feel better quality, came in a posh box with tailored made foam packaging, just looked as through it had a better start to life then just thrown into a plastic bag and then a container from China. -
https://www.ebay.co.uk/itm/Viecar-Bluetooth-ELM327-OBD2-Car-Auto-Scanner-Tool-OBDII-CAN-BUS-Android-Tourque/232314622615?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649