I've tried image 117 and it seems to work as well on the Pi 3B+ as 95. It still has many of the same issues (wifi, selection and audio). Rodney helped fix the bug where the swipe tutorial covers the screen but won't disappear (because you can't swipe like on the phones).
If you only have a touchscreen and you find your view is getting blocked by the first run tutorial then edit /var/lib/AccountsService/users/phablet so that the line starting DemoEdgesCompleted reads DemoEdgesCompleted=[‘left’, ‘top’, ‘right’, ‘left-long’]
You can do this via ssh or (with difficulty) in the terminal squinting through the tutorial screen.
If you have an hdmi monitor and connect to that it should open in desktop mode and after that it will be fine in the touchscreen next time it is run.
The Super-a Key opens the launcher just like on Gnome.

@ComLarsic Can you not log out of the GUI and then install it from the prompt?

@WLBI I'm too mean to pay £34 a month when I can get away with £14

@WLBI I pay for 2GB a month, my partner pays for 20GB a month. Data in the UK is only unlimited on expensive contracts. I have unlimited minutes and texts.

Very quick and easy to do. Access Network Settings by pulling down from the top, select Mobile Settings, Slide Cellular data to off.

@3arn0wl I use Gparted. Easy to do when the SD card is in another computer (or in a USB card reader attached to the Pi running Raspian) and you can therefore unmount the partitions to edit them. Good luck.

@3arn0wl the Telegram group is often the quickest place to get help: https://t.me/UBports_pi

@3arn0wl Possibly you just need to redo the SD card. Did you unzip the image before writing it? After writing the card did you expand the root partition into the unallocated space and did you use a beefed up power supply and connect up an Ethernet cable when trying to boot?
Seven blinks suggests that the kernel image is not found. https://raspberrypi.stackexchange.com/questions/41450/raspberry-pi-not-working/41455#41455
I've never used Etcher.

There has been a lot going on but it is only recorded in the Telegram group. https://t.me/UBports_pi
The Pi3 is working fairly well (with swap) although sound and wifi are still issues and selection (without a touch screen) has its peculiarities. Morph browser and Dekko email seem pretty stable, Terminal works a treat for installing click packages built for Arm64. Running update and upgrade mostly brings improvements but might break it so consider making a backup.

Here is what is in the Telegram pinned post:
Installing Ubuntu touch is pretty easy. The default login is phablet as is the password. It should just login itself but you will need that when using the terminal for things requiring sudo or when changing some settings in the GUI. If you can use an ethernet cable at the setup stage it avoids any wifi issues (that are being worked on). Selection by mouse is a bit buggy still, sometimes selecting with "Tab" then hitting "Return" will be easier.

Download an image from https://ci.ubports.com/job/rootfs/job/rootfs-rpi/

After image #90 (15th December) there was a change which meant that the Pi 4 graphics were broken not just on windows but on the login screen (it works but you can't see that it works on a monitor) - keep trying newer images as that will eventually be fixed. This is not a problem for the Pi 3.
Feel free to experiment with newer images and let us know your experiences but there may not be someone else to compare notes with yet.

Flash SD card:
Use DD in the Linux terminal or on windows https://www.balena.io/etcher/ to write the image to the sd card once you have unzipped it. Raspberry Pi sites will give details of how to do all this.
Remember to expand the main partition to fill the card. Easiest to use a card no bigger than 32GB.

Swap:
It works better with swap. Type sudo apt-get install dc dphys-swapfile in the terminal if you want a swap partition of 2GB

Development:
https://gitlab.com/ubports/core/rootfs-builder-debos and the multiple deb packages that are used are built on ci.ubports.com with the source on github.com/ubports/

Apps:
https://forums.ubports.com/topic/3323/arm64-apps-and-testing is a good place to start when looking for arm64 apps and how to install and test them.
Some of the arm64 apps being tested for the pinephone and other arm64 devices work, others just shut down or behave oddly. Openstore is getting more arm64 architecture apps.

Sound is not sorted yet and neither is the Pi camera. However the Pi touchscreen works. Expect bugs and crashes - we are at an early stage. Probably more Alpha than Beta testing but things are developing quickly. Wifi pretends to work but ethernet works well. Have fun and please use the UBports forums, Github or associated Telegram groups to learn more, to give feedback or to help solve bugs or other issues.

@Mark Brian Douglas now has an experimental open store for multi arch which worked well for me on the Pi. The Telegram UBports Raspberry Pi group is a good place to follow progress.