Device shuts down even though 19% battery left

Number:rdar://15056186 Date Originated:Sept 23, 2013
Status:Open Resolved:
Product:iOS SDK Product Version:iOS 7.0 (11A4449d)
Classification:Severe Bug Reproducible:Sometimes
My iPhone 5 (A1429) shut down with 19% battery why running Tweetbot and reading tweets via 3G network. Pushing the power button showed the "need to charge" pictogram. Immediately on connecting it to a charger the OS boots and shows 19% battery.

Steps to Reproduce:
1. Charge full in the morning
2. Let the device discharge until around 20%
3. Go walk the dog and surf the internet over shoddy 3G

Expected Results:
- see a battery warning 
- be able to continue to use it
- the device should shut down only when the battery is empty

Actual Results:
- no warning is shown
- the device simply shuts down (you see the spinner)

iOS 7.0 (11A4449d)

Other users report the same issue: e.g. rdar://15056120

iPhone 5 (A1429)


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!