I have used some PVC conduit for fabricating tubing for different purposes on my trike. Once you have mounted, say, a vertical piece of tubing, you can attach a phone holder (many available from Amazon).

I started with a short length of irrigation pipe, which happened to fit into the stub of my mirror mount tube. I filled the end of the pipe with gorilla glue, let it set and put a cotter pin through it to secure it. Then I slid a piece of the 3/4" conduit over the irrigation pipe stub.

This is the conduit after sliding down over the irrigation pipe. I use this for holding cue cards for the bike tours I take, but it's secure enough to hold a phone mount. The PVC has been sprayed to match the paint on my trike.


This is another method of a DIY mount for whatever you need. It's the same PVC conduit sprayed to match, and attached to the neck rest supports with zip ties. Once you get a tube secured, you can add various mounts for a Garmin or phone holder. Or you can probably get an aluminum attachment from Utah Trikes or some other outlets, but those items are not cheap.