I am the owner of an Acer T231 touch-capable monitor and a MK802 (mini Android PC). Does anyone know how to get the touch device to work? Are drivers needed for Android?
For the MK802, see the article How to re-install MK802 firmware that shows how to install (or reinstall) the firmware and from where. However, only the Rikomagic link worked for me for downloading LiveSuite and firmware Rev.1. If installing the latest firmware does not fix the problem, then it is probably caused by hardware.
For Android you will probably need to do some patch and recompile work on your kernel as described in Multitouch on Android, since the MK802 is not in the list of Available multitouch devices. As far as I understand from this article, this is easier for Android versions of at least 4.0 (Ice cream sandwich).