Unknown handheld hardware
I don't know much about this hardware, but it seems to be popularly coupled with a 1.8" low-res screen, as seen on handhelds like the BaoBaoLong BBL-380 and others.
(However, not every 1.8"-screen handheld uses it - there's also a variation of VT system or Famiclone designed for this screen size, probably developed by Wellminds)
It can also support a higher resolution display with TV out, judging from the existence of consoles containing scaled-up versions of otherwise identical games.
The most common games seen on this hardware are developed by an unknown company but can be distinguished by many factors including their use of a green menu background, mostly uniform title screens (featuring the game name in yellow-orange gradient Arial) and abundance of stolen music.