How can I keep my iPhone going on a multiday hike?

Question

Taking a five day hike, and I want to take a bazillion pictures. It would be nice to have the compass & GPS functionality too, and I want something really small. The obvious choice is my iPhone.

As everyone knows, however, an iPhone sucks juice like a baby waking up from a night's sleep. Even if I turn off all the radio transmitters, I just can't imagine my iPhone holding a charge for more than a day.

I've poked around looking at hand-crank chargers (not recommended for smart phones), and solar panels seem to have really mixed results. I've also seen chargers that take 9-volt batteries and convert them into juice, but realistically don't know how many batteries I'd need to drain to keep my electronics going.

So, what is my best option for having this device last the whole hike, with no recharge?

Answer 1

If the GPS is mostly off (i.e. you're only rarely using your GPS app), I think you will get ~2 days of battery life. To get that much battery life, you'd need to do these things:

• Keep the GPS off as much as possible (i.e. use it no more that 5-6 times a day)
• Turn it off at night completely
• keep brightness to a minimum
• Disable all cellular antennas (may need to jailbreak to do this)
• remove unnecessary apps, especially anything that wants to run in the background
• turn it off during the day as much as possible

So even with all that, you're looking at 2 days.

What can you do beyond that? I think the simplest solution to get you the recharge you'd need is to buy an iPhone battery case - usually this is just an external Li-ion battery that plugs into your iPhone. These are pretty common, fairly light, and generally easy to use. They also have the advantage of often combining in a waterproof case (so you can take pictures even if it is raining). The limitation might be that it doesn't actually get you enough charges for what you want to do (a bazillion pictures are a lot!)

I agree that hand-cranks and solar chargers are not nearly reliable enough.

So the only other solution that I might consider is something that eats AA Li-ion disposable batteries (or if you feel environmentally friendly, the best AA rechargeables you can find) and spits out power via USB. Tekkeon makes a couple products that might be the right kind of thing (I've used one before that worked perfectly)... You might try this one. Li-ion AAs are very light, although expensive, and each set of 2 will charge your iPhone 1-2 times (depends on which AA charger you get and which iPhone you have... might be best to test this before you leave!).

Answer 2

My solution is to let the phone be a phone (and GPS and web browser and ...) and take a camera to be a camera. My camera uses AA batteries, it's simple enough to bring spares, and I have a solar recharger for them too. I can take hundreds of pictures before I need to recharge the batteries. I can turn the phone on once a day or so to use the GPS or whatever, and I'm not using up phone battery when I'm taking pictures. Similarly, I'm not using up camera batteries when I'm checking to see if anyone phoned me.

I know it appears counter-intuitive - why take two things when one can meet both functions? But it works for me.

Answer 3

You could consider looking into something like the PowerPot. They are currently accepting pre-orders on Kickstarter. It is described as follows:

Simply put, the PowerPot transforms the heat from cooking into electricity (…) using a technology called thermoelectric power generation.

I’m not sure how well it will work, but from their description it seems like it could do exactly what you’re looking for. The only thing is that it doesn’t look like it’s on the market yet, although the Kickstarter site mentions deliveries for pre-orders should start in July 2012.

Answer 4

Take an external rechargeable powerpack like one of these:-

http://www.amazon.com/PowerGen-External-Blackberry-Sensation-Thunderbolt/dp/B005VBNYDS/ref=dp_cp_ob_hpc_title_1

Choose the size of powerpack according to your trip length and needs, as these things are not lightweight. Obviously, these tend to be bigger and heavier than the device you're looking to charge :-(

As an alternative, look at an Android phone. You'll get much the same feature set (GPS, compass, phone) but with the advantage of field-swappable batteries. So you can just purchase a few extra batteries, charge them up, tape over the contacts and stick them in a ziploc bag.

Answer 5

Ideally you want an independent device for your navigation. Such as a Garmin Dakota 20 or a Garmin Foretrex 401 which are both considerably cheap. On established trails you don't need that at all.

However if things go south, murphys law suggests, that your cellphone will be dead by then as well.

An external power bank (plenty of links above already) can hold up to 4+ charges and is good to have around in your normal urban life as well.

If you run your phone on airplane mode and have one of these powerbanks you should be good for up to 14 days without a gridbased power source.

Using the GPS on your phone WILL drain your battery in no time. I have an app for topographic maps. However it will use the GPS constantly, resulting in your phone being dead in 3-4 hours.

Answer 6

I'd recommend getting a solar powered charger. I go for multi-day hiking trips and I use one all the time. I ordered mine from aliexpress.com, waterproof, for less than $20. It's really inexpensive because you're ordering it directly from China and it's free shipping since China ships so many goods all around the world.

Answer 7

Have a look at these solar charger options. Solar charger solio, power traveller, brown dog, snow lizard, Bushnell Bear Grylls SolarWrap Freeloader pro / freeloader, links http://www.instructables.com/id/DYI-iPhone-5-Solar-Charger-with-CAD/ http://www.outdoorgearlab.com/Solar-Charger-Reviews

In the end I went with an option by a company called Portapow and on Amazon they were doing a 11w solar panel and usb battery bundle for £80. Batteries by Anker also come with a good reputation and portapow also have an AA USB battery charger.

Answer 8

You're a little too late for this kickstarter campaign, which covers your exact use case:

https://www.kickstarter.com/projects/ezelleron/kraftwerk-highly-innovative-portable-power-plant

It's a fuel cell that converts lighter or camping gas from standard containers to electricity for USB charging with outdoors in mind. However fuel cells aren't new. What's new is the support for standard gas containers in a portable and somewhat robust device. Earlier products required hydrogen, specific containers and/or a fixed orientation to operate.

Hope it'll hit the market in mid 2016.

Disclaimer: I'm a backer but not affiliated to eZelleron otherwise.

Answer 9

Most items have been mentioned (and I will not repeat them), but some obvious I didn't see are:

• Turn off Bluetooth
• Turn off WIFI
• Already mentioned was making the screen brightness lower. A screen is using up a lot of power. Related are:
  • Don't look more than needed on the display.
  • I assume you can define the time before the screen blank timeout (after you looked at the screen, it will turn off after some time). Minimize this time, or better, switch the screen off manually.