Dynamo Hubs

Using dynamo charging units to keep your devices charged up on an extended race, event or tour gets a bit tricky as there are many variables at play.
The simplest way to be sure you will be successful is to use your dynamo generated energy to power a power bank (battery). We had 2 customers that did the 2019 Paris-Brest Paris (1200K!) and both of them used the Power Pack II to charge their GPS & phones with success.
One of the tricky parts of using dynamo energy with devices is the constant fluctuation in power output. Many electronic devices lock onto a small trickle of power and do not take in more power when it becomes available. This leads to NOT charging the device. Some devices re-assess and take in higher levels of power when it becomes available (my iPhones have always seemed ok at this), but not all. So the only sure bet is to use a power bank that is designed to adjust intake as it is available. Not all (in fact few) power banks can handle this power management.
The Cinq5 Power Pack II as well as Goalzero Power Banks have been specifically designed not only to accept an ever-changing flow of power, but also are capable of acting as a pass-through. This means that the power bank can be used to charge a device at the same time that it is being charged.

We do a lot of dynamo lighting setups at Perennial Cycle. We have customers using dynamo power to light up their way home from work, keep them well light and fully charged on massive road rides, heading into the woods bike camping or cross country touring.
Lights for dynamo are pretty straight-forward and info can be found HERE.

Personally I've used the Plug III as well as the Igaro D2 Pro R2 to charge a few different iPhones over the years with great success, but how successful you are at charging a device with dynamo charger will depend on the amount of daylight you have (dynamo chargers do not charge AND run your lights), the device you are charging and the speed you ride at.
If you have time, it is best to do a fair bit of testing.