I'll try to post some pix of my helmet mount later. And I plan to get a smaller external battery, one of the cylindrical ones to fit in an adjacent helmet vent. My current USB battery, a Jackery, is a bit large for helmet mounting. I've done it, but it's awkward and feels a bit heavy up there.

Regarding the firmware or operating system glitch, that seems to be a quirk with some action cams -- not just the Ion. Mobius has a whole page on troubleshooting stuff like this. Ion doesn't, but a customer service chat helped resolve the glitch.

First, be sure to use a high quality Class 10 card. Sandisk, Lexar, Kingston, a few others are all reliable. But Sandisk and Lexar cards have been counterfeited so it's hard to be sure you're getting the genuine article.

Reformat the card in the PC. Usually this will clear up glitches. When you reinsert the media card into the camera and turn it on, the operating system will automatically reinstall on the card. The OS and installation routine are built into the camera itself and should be fully automated.

Open the OS to get the customizable features. I usually resync the date/time every time I use the camera because it tends to be off about 15 minutes or so a day.

The Ion customer service tech said it shouldn't be necessary to reformat the card after every use, so I just delete the files after copying whatever I want to keep to my external hard drive. Usually I just delete ride videos if nothing interesting happened.

One persistent glitch I've experienced is the camera tends to shut off within two minutes after first turning it on. The customer service tech suggested trying a new card but I haven't gotten around to that yet. It only happens occasionally but can be annoying when the camera is on my helmet and I don't notice. So I've gotten into the habit of turning it on while I'm getting set to ride, then rechecking at the curb before riding away. If it's still on after two minutes it should run continuously until the battery is exhausted or the card is full.

But when I really need to record reliably I'll mount it on the handlebar where I can keep an eye on that red recording light.

A couple of weeks ago I rode my bike to the local women's march/rally on January 21. I forgot the helmet mounted cam was still running, but it recorded some interesting stuff from a higher than average point of view. I was also taking still photos and might combine the two into a video.