I have a pinebook with the original installed ubuntu 16.04.
Is it possible to update this device to 18.04? I don't know if there are some modifications. And additional, i never used ubuntu before, how shall i do, if it is possible?
Go for the bionic desktop build, that is 18.04. Backup your data first.
If you want to upgrade through the OS, it is possibly going to wear down your flash card with many writes, take a long time - and if it goes wrong and you find a migration blocker, you are probably on your own.
But if you want nevertheless try it, then probably the following would apply.
formatting link
What doesn't work that you need 18.04 for tinkering?
If you want to try Ubuntu for being a desktop OS (i.e. not tinkering), wouldn't a machine of better class (more grunt) make more sense?
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