iPhone SE - iOS 11.2.1

Aircraft Firmware: V 01.00.0900
Remote Controller Firmware: V 01.00.0400
DJI GO 4 App iOS: V 4.1.20

AC and RC batteries 100% when starting. Phone battery around 90%.

All other apps in phone closed.

In Beginner Mode.
Compass ok.
GPS 11 or more.
RTH set.
Pre flight checks.

Phone connected to RC Wi-Fi. AC hovering, maybe doing a small adjustments. Not going in any direction at any speed.

Everything going ok.

After maybe 11/12 mins of flight my iPhone notified me it was going into Low Power Mode. No way this could be accurate.

AC response to remote control stick inputs then seemed delayed. Video was delayed and pixalated. For example, move the gimbal and the response was not instant. It was seconds but I couldn't say exactly how many.

My iPhone then shut down. I did not power it down. I knew there was no way the battery was that low in 12 minutes. When I restarted the phone it was at 44% battery.

All flights before and a few test flights since have been ok. I'm only flying around outside the house at the moment.

Is what happened above possible because my phone lost its 3G data connection in flight?

Reason I say it is because I live in a poor 3G area and use a Vodafone Sure Signal V3 (femtocell) device around the house.  The electricity supply in the local area went off while in flight so my phone would have lost its 3G and its connection to DJI.

  
  

The first thing I would do is get the “battery life” app from app store, to check how worn the phone battery is.
IOS is known to slow the phone down if the battery is tired.

heliman Posted at 2017-12-30 10:35
The first thing I would do is get the “battery life” app from app store, to check how worn the phone battery is.
IOS is known to slow the phone down if the battery is tired.

To diagnose of course I will try this. I am aware of the current issues Apple are having with older phones and batteries. But it's not really the phone that slowed down.

I wonder if the DJI GO 4 app crashed or caused the phone to crash when it lost comms with the DJI servers?

Battery Life is reporting "Battery Wear Level" at 1% which is says is "Very Low"

Just spotted this from another user. Similar circumstances. It was maybe 7 to 10 degrees celsius for me.

https://forum.dji.com/thread-126888-1-1.html

Yes the cold could explain it.
Otherwise I would check iphone settings, battery (scroll down a little) to se if the go app is the worst power hog. It probably is.
I don’t think the 3G issues can do it.

I have the exact same setup, except for I am not in beginner mode and I force the spark to use a free 2.4GHz channel.
My video feed works fine, except when I am at home near my wifi hotspots. My iphone SE is good for at least 5 flights.
My old iphone 5s (no sim card) also works well.