If you want to get more documents and demos' source code for pcDuino8 Uno, please check the following websites.
This is the github repository collecting documents and demos about pcDuino8 Uno and let user quick start OpenCV computer version on pcDuino8 Uno. Use git to download:
$ git clone https://github.com/pcduino/pcduino8-uno-guide
This website has collected different system image for pcDuino8 Uno, including Ubuntu and Android.
This website has been collected many posts on pcDuinos, not only pcDuino8 Uno.
4. Forum
If you have any question, please post it there, LinkSprite Engineers will try their best to answer your questions.