There have been a number of threads talking about people having issues with iPhone battery life (especially in cold temperatures).

  
  

Here's my experience: I have flown a number of times at 0F to 18F (-18 to -8 Celsius)  (each time the Mavic rode folded in backpack exposed to the cold but the battery had a warming pack on it to keep it warm.)  In each case (up to 18 minutes of flying) I had no problems with Mavic or RC battery life. My iPhone 6 was another story. I started out with all batteries fully charged and the iPhone turned off.  I kept the iPhone somewhat warm in an inside pocket and the iPhone started at 100% charge but during the longer flights it would be down below 20% each time (once below 10%).  The iPhone (at least in my case) is the weak link for cold temperature flying.  There seems to be no issue in warm (> 40F) temperatures. I have since experimented with some changes and am now able to get more life out of my iPhone.

  
  

I'll share my results here but would like anyone else that has had iPhone battery issues to share their tips here as well. Thanks!

  
  

My tips:

  

1) I keep my iPhone fully charged by plugging in to a USB port in my car as we drive tot the trail head.

  

2) I shut down the iPhone for the hike to the trailhead (I pre-load the maps to DJI Go 4 or Litchi)

  

3) I put the iPhone in an inside pocket with a warming pack. (The warming pack seems to really help).

  

4) I have disabled caching of videos (DJI Go/Litchi) on the iPhone.

5) Turn off wifi, cell reception and bluetooth (airplane mode)  

6) I have uninstalled the Facebook App. This one surprised me but I noticed a pretty good improvement in my (only two) tests so far. Here are some details on disabling the FB app but keeping FB one button press away:   

http://www.howtogeek.com/239363/forget-the-facebook-app-use-the-mobile-site-for-a-less-annoying-experience/

7) Attach warming gel pad or chemical warmer to the back of the cell phone while it's use (attched to the RC). A good example is this at less than 1 USD each.

https://www.amazon.com/HotHands- ... rmers+with+adhesive   

Edit: update Jan 29, 2017: I have since tested the adhesive body warmers on the iPhone and these seem to work great. The phone works as if it's running in warm temperatures.

(Edit: added step 5 for Airplane mode and step 7 for stick on warmers)

This weekend I had similar issues with the iPhone giving up, despite having a 100% charge at the start. By my third aircraft battery it was toast. My wife picked up some mitten warmers at a ski shop which got me wondering if a couple elastics around the phone and a warmer on the back might help, but not sure if that'd run it too hot. Otherwise the phone gets cold quickly — and I was only shooting in weather that went from -1C to +3C.
Wonder if these warmers might also be an option to put on my spare aircraft batteries. Otherwise, I had a battery in an inner pocket thinking that would be warm enough, but got a message saying that it was too cold to fly, when I swapped it into the Mavic.

GMG Posted at 2017-1-9 13:59
This weekend I had similar issues with the iPhone giving up, despite having a 100% charge at the start. By my third aircraft battery it was toast. My wife picked up some mitten warmers at a ski shop which got me wondering if a couple elastics around the phone and a warmer on the back might help, but not sure if that'd run it too hot. Otherwise the phone gets cold quickly — and I was only shooting in weather that went from -1C to +3C.
Wonder if these warmers might also be an option to put on my spare aircraft batteries. Otherwise, I had a battery in an inner pocket thinking that would be warm enough, but got a message saying that it was too cold to fly, when I swapped it into the Mavic.

Cheers for those trip, Im heading to Norway in a few weeks and was concerned about the equipment and the cold temperatures.... If you come up with any other advice please do let us know.....

GMG Posted at 2017-1-9 13:59
This weekend I had similar issues with the iPhone giving up, despite having a 100% charge at the start. By my third aircraft battery it was toast. My wife picked up some mitten warmers at a ski shop which got me wondering if a couple elastics around the phone and a warmer on the back might help, but not sure if that'd run it too hot. Otherwise the phone gets cold quickly — and I was only shooting in weather that went from -1C to +3C.
Wonder if these warmers might also be an option to put on my spare aircraft batteries. Otherwise, I had a battery in an inner pocket thinking that would be warm enough, but got a message saying that it was too cold to fly, when I swapped it into the Mavic.

I think that may work. I don't think it would be too hot (assuming it's pretty cold outside).  

RenMai Posted at 2017-1-9 14:33
Cheers for those trip, Im heading to Norway in a few weeks and was concerned about the equipment and the cold temperatures.... If you come up with any other advice please do let us know.....

Thanks! I am hoping others will have their own ideas on this and offer their ideas here.

I have this setup. Haven't used for Mavic / iPhone yet, but seems to stay toasty inside.   Large viewing window gives a clear picture of iPhone or iPad.

https://hobbyking.com/en_us/turn ... eckstrap-ready.html
https://hobbyking.com/en_us/hobb ... -heater-system.html

Sorry, no tips from my limited experience. I am having the same iPhone 6 battery life issue. AC and RC no problems.

Cold weather flights starting with iPhone at 100% charge (iPhone and RC/AC were at room temperature 70F two minutes before takeoff):
5:53 minute flight at 10F ended with iPhone low battery warning then iPhone turned off right before landing (cache ON).
6:09 minute flight at 20F ended with iPhone low battery warning and iPhone at 1% at landing (cache OFF).

At this point thinking about an iPhone battery replacement or perhaps buying an iPad mini 4, or just waiting for warmer weather

Have you experienced any improvement with your iPhone 6 battery life at warmer temperatures?

ScreamMaker Posted at 2017-1-9 18:31
Sorry, no tips from my limited experience. I am having the same iPhone 6 battery life issue. AC and RC no problems.

Cold weather flights starting with iPhone at 100% charge (iPhone and RC/AC were at room temperature 70F two minutes before takeoff):

Yes, at warm temps the iPhone does great. Try my suggestions above. They should help.

ScreamMaker Posted at 2017-1-9 18:31
Sorry, no tips from my limited experience. I am having the same iPhone 6 battery life issue. AC and RC no problems.

Cold weather flights starting with iPhone at 100% charge (iPhone and RC/AC were at room temperature 70F two minutes before takeoff):

Yes, at warm temps the iPhone does great. Try my suggestions above. They should help.

I had a great suggestion from over at MavicPilots to use a stick-on body warmer.  I did a search on amazon and found this:

https://www.amazon.com/HotHands- ... rmers+with+adhesive

You could stick this to the back of the iPhone while it's attached to the RC. I haven't tried this yet but it should work (and I'll try it soon).

WolfgangStiller Posted at 2017-1-12 18:04
I had a great suggestion from over at MavicPilots to use a stick-on body warmer.  I did a search on amazon and found this:

https://www.amazon.com/HotHands-Adhesive-Body-Warmer-count/dp/B005J2K356/ref=sr_1_1?ie=UTF8&qid=1484272315&sr=8-1&keywords=body+warmers+with+adhesive

Thanks for sharing, will certainly give it a try. My last flight in warmer 51 degree weather was much better as you suggested it would be. Flight time of 20 minutes took iPhone battery from 100% to 68%. Definitely appears it was mainly a cold weather problem with the iPhone so a hand warmer like this should be very helpful.

ScreamMaker Posted at 2017-1-12 19:07
Thanks for sharing, will certainly give it a try. My last flight in warmer 51 degree weather was much better as you suggested it would be. Flight time of 20 minutes took iPhone battery from 100% to 68%. Definitely appears it was mainly a cold weather problem with the iPhone so a hand warmer like this should be very helpful.

It's clearly a cold weather issue. I  have done lots of flights in wamer temps with no issues.  I think the reason t he iPhone suffers more is that it's so thin and the battery is right close to the surface so the cold gets in very quickly.    The aspect is why IOS phones are affected more than Android and that's got to be the charging issue. Android phones will charge from the RC but iPhones won't. This can be good or bad depending upon your perspective.I know some Android users are complaining that their phones are drawing down the battery in the RC.  Personally, I'd prefer to have the iPhone charged from the RC since the RC has a much bigger battery.

I ordered now this  and hope it works. My former solution is an adhesive phone wallet like here
That works great, such a handwormer into the pocket and your phone stays warmer  :-)

D_jan_i Posted at 2017-1-19 18:47
I ordered now this  and hope it works. My former solution is an adhesive phone wallet like here
That works great, such a handwormer into the pocket and your phone stays warmer  :-)

Please report back on how well it works for you.  I was concerned that it's not a good fit for Mavic RC since it seems to be designed for an RC with a single antenna.  

So people are willing to take all these steps but not willing to just buy a new phone or tablet? There's an issue with iphone batteries... why struggle with it?
I ditched my iphone the day I found out about the recall. My phone wasn't covered so it got sold. I suggest you do the same and save yourself the stress of it dying mid-flight.

SpeedVision Posted at 2017-1-9 18:10
I have this setup. Haven't used for Mavic / iPhone yet, but seems to stay toasty inside.   Large viewing window gives a clear picture of iPhone or iPad.

https://hobbyking.com/en_us/turnigy-transmitter-glove-2-4ghz-neckstrap-ready.html

I have used my setup above in 32F temperatures.  Had to turn down the temp to keep my hands from sweating.  Place it right under the iPhone/controller and stays nice an toasty.  Need a 3s lipo or a 12v lead acid to power.  In my case, I have 3s lipo's galore, so no worries.  DO NOT use the Mavic battery adapter USB thingy as the heater draws too many amps.  

IMO, without a heat source, a transmitter glove is not enough.  

WolfgangStiller Posted at 2017-1-20 06:38
Please report back on how well it works for you.  I was concerned that it's not a good fit for Mavic RC since it seems to be designed for an RC with a single antenna.

I will test next week and keep everybody posted. I guess the top is the side you can open - hopefully I'm right  ;-)

SpeedVision Posted at 2017-1-20 08:35
I have used my setup above in 32F temperatures.  Had to turn down the temp to keep my hands from sweating.  Place it right under the iPhone/controller and stays nice an toasty.  Need a 3s lipo or a 12v lead acid to power.  In my case, I have 3s lipo's galore, so no worries.  DO NOT use the Mavic battery adapter USB thingy as the heater draws too many amps.  

IMO, without a heat source, a transmitter glove is not enough.

Nice. Sounds like a very elaborate setup. How heavy is it? Does it take up much room?

WolfgangStiller Posted at 2017-1-21 10:28
Nice. Sounds like a very elaborate setup. How heavy is it? Does it take up much room?

Glove flattens out  and the diameter is a little bit larger than the Mavic with arms extended . Heater is quite small. Whole setup  weighs less than a pound. Then you'd have the weight of whatever battery your bring.  The clear section works OK… Regardless, I don't think there's a better way to keep your hands in the electronics warm during flying.

I just had a similar experience not quite as bad but still - iPhone 6S plus - 3 batteries and the phone was down to 4% ... seeing this I would consider the iPhone not fit for purpose to be honest - interestingly I still have a Note 4 around that I used for some testing yesterday and saw that an Android device actually is being charged by the remote unlike an apple device  ...

going into flight-mode doesnt help anything as this usually disables live-map updates and other things I would still like - I guess I need to by another Android device for this ...

r4nd0m Posted at 2017-1-22 08:42
I just had a similar experience not quite as bad but still - iPhone 6S plus - 3 batteries and the phone was down to 4% ... seeing this I would consider the iPhone not fit for purpose to be honest - interestingly I still have a Note 4 around that I used for some testing yesterday and saw that an Android device actually is being charged by the remote unlike an apple device  ...

going into flight-mode doesnt help anything as this usually disables live-map updates and other things I would still like - I guess I need to by another Android device for this ...

Did you try doing anything to warm the iPhone? I think once you do that, you will be able to get a lot more flying time. I have been experimenting with stick-on body warmers and they seem to work great. Getting what seems like a lot more time but haven't flown in the really cold temps (below 10F)  with the heaters yet.

WolfgangStiller Posted at 2017-1-23 09:33
Did you try doing anything to warm the iPhone? I think once you do that, you will be able to get a lot more flying time. I have been experimenting with stick-on body warmers and they seem to work great. Getting what seems like a lot more time but haven't flown in the really cold temps (below 10F)  with the heaters yet.

no I did not but I shouldnt need to either - the phone works perfectly fine when watching video/netflix out in the cold so this shouldnt impact it ...

there seems to be an issue with the 6/6S though so I upgraded to a 7 and will test over the weekend, if not I may use the ipad mini that I got for the inspire .. lot of options to try out ...

canadianairborn Posted at 2017-1-20 06:51
So people are willing to take all these steps but not willing to just buy a new phone or tablet? There's an issue with iphone batteries... why struggle with it?
I ditched my iphone the day I found out about the recall. My phone wasn't covered so it got sold. I suggest you do the same and save yourself the stress of it dying mid-flight.

Wait what?  Are kidding.  So let me get rid of a $500 plus phone, and totally switch platforms over to android, because the battery dies quickly in bitterly cold weather, while flying my Drone (maybe couple times a week).  That makes perfect and complete sense.

On the other hand maybe all the android guys should switch over the iPhone cause the DJI Go app is way more stable on IOS.  I'm sure that would make perfect sense for all of them as well..

I'm on iPhone 7, I set the "low power mode" before I leave the house to extend the battery life. Also fly in airplane mode to reduce draw during the flight. Flown many times over the last week in Norway in temps down to -7 Celsius. I also have a case on the iPhone, not sure that helps but I figure it has to. One thing tho the Mavic complained its own batteries were under 15degs..in that case I just took off and let if hover for 5 mins till the battery temp reached about 19 degrees.

Got another tip from a user on FB on the iPhone power issue. He says that doing a reboot (power off and back on) or powering totally off before leaving power makes a big difference. I haven't tried this yet so I haven't added this to the main tips list but thought I'd pass this along for what it's worth and see if it works for anyone else. I am going to try it myself but it will be hard to tell unless I have a good basis for comparison. If anyone else tries this let me know how if it makes a difference. Thanks!

I have found some tips for how to Improve iOS 11 Battery Life On iPhone

shanicosta Posted at 2017-7-25 22:15
I have found some tips for how to Improve iOS 11 Battery Life On iPhone

Thanks for adding this valuable link.  I am holding off on using (beta)  IOS11 with DJI Go4. Have you tried this?

WolfgangStiller Posted at 2017-1-13 12:16
It's clearly a cold weather issue. I  have done lots of flights in wamer temps with no issues.  I think the reason t he iPhone suffers more is that it's so thin and the battery is right close to the surface so the cold gets in very quickly.    The aspect is why IOS phones are affected more than Android and that's got to be the charging issue. Android phones will charge from the RC but iPhones won't. This can be good or bad depending upon your perspective.I know some Android users are complaining that their phones are drawing down the battery in the RC.  Personally, I'd prefer to have the iPhone charged from the RC since the RC has a much bigger battery.

What would be better, an empty phone battery or an empty RC battery? I'd prefer a empty phone battery so I can still land the MP...

Mari Posted at 2017-8-2 11:50
What would be better, an empty phone battery or an empty RC battery? I'd prefer a empty phone battery so I can still land the MP...

I agree. That said, the RC battery is a much bigger battery so it would be reasonable to use some of its power for the iPhone.

Warranty replaced my iPhone 6s battery during cold winter did massive improvements for me. I also got rid of the iPhone shutdown due to low battery when it could be 50% left. So I got the feeling the IPhone shipped with a none cold climate issue by default and Apple Store had no problem replacing IG

fansb8b222f3 Posted at 2017-8-2 13:36
Warranty replaced my iPhone 6s battery during cold winter did massive improvements for me. I also got rid of the iPhone shutdown due to low battery when it could be 50% left. So I got the feeling the IPhone shipped with a none cold climate issue by default and Apple Store had no problem replacing IG

Good to know about Apple supporting this in terms of warranty! Thanks!