iPhone Battery usage always shows standby and usage as same

I had this problem for awhile on iOS 7 several months ago. It turned out to be a "rogue" app that was running often enough in the background to count the time as running rather than standby, even though the battery life was still excellent. In my case it was the DataMan app that monitored the data usage of my cellular data plan. I ended up just deleting the app since the Apple IOS provides essentially similar data.

I've had no problem since deleting the app, even after converting to iOS 8.

The way to find out the app that is causing it is to use the double click (or 4 finger swipe) to find all the running apps. Then turn them off one at a time via an upward swipe until you find the one that is causing the problem. This will take awhile, but it worked for me.

 

What model do you have?
Apple has determined that a very small percentage of iPhone 5 devices may suddenly experience shorter battery life or need to be charged more frequently. The affected iPhone 5 devices were sold between September 2012 and January 2013 and fall within a limited serial number range.

If your iPhone 5 is experiencing these symptoms and meets the eligibility requirements noted below, Apple will replace your iPhone 5 battery, free of charge.

Enter your iPhone serial number at

https://www.apple.com/support/iphone5-battery/

 

Do you have anything that you leave on in the background? Mine is that way, but I run Human in the background all the time. It eats very very little battery, but always shows as "in use" for the battery usage times.