Made up of a 12cm (4.75inch) turbine, a 5W generator and a built in 5000mAh battery, when put in running water it will charge your devices via the USB 2A and 1A ports, or store the energy for later use.
Blue Freedom says that the micro turbine does not need to be placed specifically in relation to the direction of the current, and is instead designed to circulate water and provide efficient charging.
The company states that it should charge its internal battery of 5000 mAh in 3 to 4 hours, assuming a water flow rate of 1.2m/sec (4feet/sec). So you could recharge an iPhone in about 1-2 hours.
Depending on the nature of your trip, this little hydropower plant may or may not be more convenient than other chargers.
It could be a good solution provided your have a suitable stretch of stream or river nearby, and you will be staying near it long enough to recharge your device or the internal battery.
The device will retail for around $319US when it launches in Oct 2015, but you can preorder on the Kickstarter starting at $219US.