Just tried out the nightly build. I noticed that there is a line of green pixels at the very bottom of the screen and there is tearing when moving windows or when interactive elements open on the display (e.g. in a browser). I have seen this before - it was also present in the very first build of the ubuntu image that shipped with the initial production units of the Pinebook.
I believe that this issue is somehow related to the refresh rate - ayufan's Linux and Android images both report 56hz, while the old Pine image and the current nightly armbian image report running at 60hz.
This is strange, because I am convinced that the Prototype unit I had ran at 60hz (cant check right now, because its dead) and the issue described above was not present. Perhaps someone more tech literate may have an insight into why this is happening.