My iPhone 6, running iOS 9.2.1, does a very strange battery thing. First off, I'm happy to share that my phone's battery sucks. I pretty much leave it plugged in now whenever I can. Sometimes the battery charge depletion is super rapid! On several occasions, my iPhone has gone from battery charge in the upper 20 to lower 30 percent range, then immediately down to zero and bricks. Plugging it back in, the battery charge indicator reflects low 20 or low 30 percent range after only 10 seconds of charge. WTF is going on? I pretty much now treat 50% like 5%. When my iPhone gets to 50%, I'm now desperately running around looking for a charger to get get it back up into 75-100% safe zone. Thanks! --- Post Merged, Feb 20, 2016 --- It should be noted I have never jailbroken my iPhone, I regularly shut down all the background running apps and do re-boots on a regular basis (weekly or bi-weekly). I've also run my battery to zero via use since I've had this issue. Nothing seems to change it.