Do I Need to Replace My iPhone 6 Plus Battery?

iTech Wireless repairs mobile phones and tablet devices.
11/28/2017 4:34:38 PM
I bought my iPhone 6 Plus in mar 2016 and am running iOS 10.3.1. My battery cycle in july of 2017 was around 400. At this point is should be closer to 500. According to the battery life, the wear is average. This is when a full charge showing of 100% is about 2500/2915mAh or 80% of the actual battery capacity. Now the issue is that when I use my phone for about 10 minutes in the AM (starting at 100%) the battery goes down quickly to 90%. Do I need to replace the battery or do I have more time to use this battery?

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