@demokrit:
Thank you very much for replying! At the end I found a post in the forum where the "magic-device-tool" was mentioned. Tried that, and: Working!

Hello!
I'm new to this and my english isn't good. After years using Ubuntu on my laptop I now tried to install U-Touch on my nexus 4, but I only get to "Ubports Recovery". How do I have to go on from there?
Thanks in advance for every help!

Edit: I managed to reinstall Android (following this page: https://docs.ubuntu.com/phone/en/devices/reinstalling-android)
But that's not what I wanted...
I'll go on trying to get UT on my phone...

Hello!
I'm new to this and my english isn't good. After years using Ubuntu on my laptop I now tried to install U-Touch on my nexus 4, but I only get to "Ubports Recovery". How do I have to go on from there?
Thanks in advance for every help!