@stefano Hi, I have just typed this command ubuntu-device-flash --server=https://system-image.ubports.com touch --device=turbo --channel=ubports-touch/16.04/stable thinking that my phone is not connected to a laptop... but it was. I have flashed UBPorts OTA-4 on my Meizu Pro 5. Thanks a lot!

Is this something interesting for UBports?

https://www.indiegogo.com/projects/cosmo-communicator/#/

Since they promise to be able to run Debian on it, it should be possible to port UBports onto...?

I see the command I entered is not complete.
I have flashed a new recovery on fastboot mode.
Then I followed with complete command:

$ sudo ubuntu-device-flash --server=http://system-image.ubports.com touch --device=turbo --channel=15.04/stable --bootstrap --recovery-image=./recovery-turbo.img
2017/12/06 16:13:15 Device is |turbo|
2017/12/06 16:13:15 Flashing version 2 from 15.04/stable channel and server http://system-image.ubports.com to device turbo
2017/12/06 16:13:19 Waiting for device to enter recovery mode ...
2017/12/06 16:13:29 Start pushing /home/andrzej/.cache/ubuntuimages/gpg/image-signing.tar.xz to device
2017/12/06 16:13:29 Start pushing /home/andrzej/.cache/ubuntuimages/ubports-touch/15.04/stable/turbo/version-2.tar.xz to device
2017/12/06 16:13:29 Start pushing /home/andrzej/.cache/ubuntuimages/pool/keyring-4c4e7ef380ebcfa2c31084efa199138e93bfed8fc58aa3eb06bdf75a78af9b57.tar.xz to device
2017/12/06 16:13:29 Start pushing /home/andrzej/.cache/ubuntuimages/gpg/image-master.tar.xz to device
2017/12/06 16:13:29 Start pushing /home/andrzej/.cache/ubuntuimages/pool/device-60f53a5768e9340729d3a5ef9263bd3a9726792e7d0dbf830e5b124938dd419a.tar.xz to device
2017/12/06 16:13:29 Start pushing /home/andrzej/.cache/ubuntuimages/pool/ubports-03a48725ab23059f103ccbb3cfa913f1ebcd314aaa0742e9ff724ee4fef19d78.tar.xz to device
2017/12/06 16:13:29 Done pushing /home/andrzej/.cache/ubuntuimages/ubports-touch/15.04/stable/turbo/version-2.tar.xz to device
2017/12/06 16:13:29 Done pushing /home/andrzej/.cache/ubuntuimages/pool/keyring-4c4e7ef380ebcfa2c31084efa199138e93bfed8fc58aa3eb06bdf75a78af9b57.tar.xz to device
2017/12/06 16:13:29 Done pushing /home/andrzej/.cache/ubuntuimages/gpg/image-master.tar.xz to device
2017/12/06 16:13:29 Done pushing /home/andrzej/.cache/ubuntuimages/gpg/image-signing.tar.xz to device
2017/12/06 16:13:50 Done pushing /home/andrzej/.cache/ubuntuimages/pool/device-60f53a5768e9340729d3a5ef9263bd3a9726792e7d0dbf830e5b124938dd419a.tar.xz to device
2017/12/06 16:14:23 Done pushing /home/andrzej/.cache/ubuntuimages/pool/ubports-03a48725ab23059f103ccbb3cfa913f1ebcd314aaa0742e9ff724ee4fef19d78.tar.xz to device
2017/12/06 16:14:23 Created ubuntu_command: /home/andrzej/.cache/ubuntuimages/ubuntu_commands002121213
2017/12/06 16:14:23 Rebooting into recovery to flash

And it's back to life.
Unfortunately I have wiped it with this. But it's good to wipe it from time to time