What firmware is supported?
V3.3.1343 or newer is currently supported.
Do i really need at least Android 4.x?
Older version support is only experimental. I'm not using any specific features not supported on older versions.
However i tested it on 2.3 and there were few UI issues with video player view which made the app badly usable.
I'm not sure how many issues are related with 2.2 or 2.3. Anyway i believe it's time to upgrade your device.
It's more than 2 years what Jelly Bean has been released.
What Media Player should i use?
Use whatever works better for you. Android nativaly supports codecs necessary to play PCTV stream. Unfortunatelly some devices (specially from Samsung)
have changed Android Media Player Core and it's not supported. Exactly for this reason i added VLC engine. So if your device can't play TV with default Android player,
try to select VLC engine. If you can't still watch your TV stream, please contact me.