I knew when I got my Catrike Pocket I'd need to devise a setup to mount and charge my iPhone.
For the phone mounting purposes I used a Rokform Pro Series iPhone Bike Mount. I have used Rokform cases to protect my phones from myself back to my iPhone 5 days. The cases offer a mechanical mounting system and a magnetic mounting system, and uses the two in combination for the bike mounting system to make your phone extra secure[^1].
As I've mentioned here before, when I go out riding my iPhone gets heavy use. I use Cyclemeter to track my speed, distance, and route, and that involves having the screen lit throughout the ride so I can get the feedback from the app. I'm also typically playing either an podcast or an audiobook to headphones over Bluetooth. These are battery intensive tasks and, especially on longer rides, even a fully-charged, plus-sized iPhone may run low. Since the phone is also my lifeline if I run into trouble, I need it to remain functional throughout the ride. This means I need a way to charge the phone during the ride.
On my Cannondale I put together a fairly basic setup using a USB cable and a Mophie Powerstation dropped into the bike's frame bag. This worked well enough, and I've used a variation of that setup for a little while on the Catrike, with a battery pack in one of the saddlebags. But I wanted to improve on this arrangement. Last fall I picked up a battery with a solar panel. While it takes some time to fully charge using the solar panel alone, once it has an initial charge the solar panel can defray the power loss and extend the length of a charge. I have a rear rack on the Catrike, so it wasn't much of a leap to put the battery out in the sun on the rack.
I originally tried strapping the battery to the rack using elastic straps. Unfortunately the straps blocked some of the solar panel and, worse than that, rattled like crazy on the aluminum rack. My solution for this was Velcro. Specifically, getting a roll of Velcro with an adhesive back and set the soft side on the rack.
To connect it all I ran a 10 foot braided nylon lightening cable up through the seat and attached it to the frame at either end using Velcro wrap thin ties[^2]. 10' is longer than I need for this application, but I like having the extra, so I have the extra coiled up in the saddlebag.
The result of this? After getting everything set up I took my Sunday ride. I was out for a little over an hour. I ran the screen the entire time, bright enough to see it in full sunlight, using Cyclemeter (which runs the gps), and listened to an audiobook. I stopped a couple of times to take pictures along the way as well. When I arrived at the end of the ride the phone battery was at 100%, and the battery pack on the back of the trike was at 75%. This suggests I probably could have ridden another three hours before I put a dent in the charge on the phone itself. The Velcro attachment worked a treat - my ride was 14+ miles, and included some gravel. I heard no rattling, and came home with the battery firmly attached.
Because of where the phone sits, my right leg hides the bottom part of the screen at times when I'm riding. Still, while it's close I don't actually hit the phone, and Utah Trikes seems to make additional attachments that I could consider for mounting the phone down the road. For the moment, it appears to work well enough.
Until and unless I start on much longer rides, I think this will work well. And, as far as that goes, there is room on the rack for at least one more battery. All in all, I'm pretty happy with this arrangement.
[^1]: I've used a variation of this on my Cannondale - the bike mounts are built to work with the top cap of a 1/8" threadless tube, which is common on modern bikes, but predates my vintage Cannondale, so there I used the Rokform motorcycle mount attached to the handlebar. The motorcycle mount is more expensive, though, so I was pleased that the 1/8" threadless mount worked for the Catrike.
[^2]: These are sort of like reusable Velcro tie wraps. They come in rolls of 25 wraps, and once you have them you'll find dozens of uses for them around the house. They are pretty awesome.