We used one of these on sani2c for charging garmins;

http://www.ebay.co.uk/itm/Duracell-Pocket-Charger-/141335830198?_trksid=p2054897.l4275

works off aa batteries unlike powermonkey type devices

Been using an auxillary power pack for a few months and have been really impressed

Typically get 3 or 4 charges out of it

If i'm using the GPS tracker function, i'll set the phone on aircraft mode to save juice

After some searching i found the one i bought - bargain at £17

Search for Anker® Astro 5600mAh Portable External Battery Charger on Amazon

Enjoy 🙂

aldi had some 12ah ones acouple of weeks ago£15

External battery and turning the phone off occasionally. At least turn it off overnight.

Powermonkey, comes with own solar panel. Easy charge everything, phone, iPad, GPS.

I bought one of the Aldi Envio 7800mAh chargers a few weeks ago on a whim, it's got 1A charging output and a 2.1A charging output along with a decent little built in LED light, it managed to charge 4 iPhone 5S iPhones from dead to full last weekend and still had enough charge to kickstart another to half full.

Not bad for the pittance it cost, i'm sure the Anker versions on Amazon are very similar or perhaps better.

Wow - something approaching a consensus - thanks everyone for your help! Will start looking into these various devices. Cheers!

Luxury of s****y hotels or a good B&B, with mains sockets and free WiFi for me, or no riding 😛

Dynamo with USB port

wild camping = phone off/at home surely?

Edit - just realised, you'll probably want to check with the STW-ers what to have for dinner/breakfast each day. Of course, that'll depend on what pedals you have, the alignment of the moon, and how many spacers under your stem...

I use a dynamo hub connected to a USB charger - you only get a constant charge at about 15kph and above so it's great on road, but for stop/start mountain biking a charged up cache battery (or two) would be more reliable.

How about buying an old nokia with a battery that will laat a week? Just use your existing sim card in it.

No use if you're actually looking to use the smartphone functions of your phone of course!

Beaten to it by murf, I've got a Nokia 105, battery lasts a week, you can pick one up cheap as chips.

Thanks m360 - there's always one 😉

Murf - not a bad call. Certainly won't be checking emails. I have a spare battery for my phone but will be lucky to get two days from each battery. Might get away with it, but don't want to find out it's not enough in the middle of nowhere surrounded by rising water and my bike broken! A third battery might be a weight (and cost) effective option.

Dynohub. B+M USBWerk. Anker 13000mAh backup battery.

Cheaper still would be a Nokia brick/phone/torch that lasts at least week on a charge 😉 (no internet can be a major bonus)

Stupid question - is there a better way of dynamo cable routing on a suspension fork than just cable-tying the wires to the fork leg?

You may be able to tape it to the front brake hose, not ideal but may keep the wires a little neater.

You may be able to tape it to the front brake hose, not ideal but may keep the wires a little neater.

Is there not a slight problem with that? 😛

Just in case you thought about ignoring the ones suggested, and decided to go to Maplins for their 10k mAh one for £30 thinking it would be better -- Don't -- It's a pile of shit.

Thanks tubthumped! Swaying towards cheap phone now, especially if I can get one with the same batteries I use in my Nokia Asha...