Apple iPhone 6s Plus
As specified by Apple
Talk time: up to 24 h with UMTS (3G)
Internet use: up to 12 h with 3G, LTE or WLAN
HD video playback: up to 14 h
Audio playback: up to 80 h
Standby time: up to 16 days
Built-in rechargeable lithium-ion battery with 2750 mAh
Charging via USB to computer system or power adapter
My own Experience
I will add some data soon, but the device is too new for writing accurate data now.
To make analyse possible I make screenshots every day since day one and I write the charging times into my calendar.
Battery running time depents from how you are using the iPhone. By very low use but hearing music 3 hours daily it lasts 2 days with approx. 40 % remain.
In order to avoid stressing the battery I usually charge it up to an maximum of 85 % and use it until a remain capacity of approx. 30 %.
Therefore my indications of battery performance are not excessive.
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