Battery Dies Very quickly
I have iPhone 6s but stop low power mode my battery drops very quickly about wondering if you battery iPhone7 to put on iPhone 6s
3min in Snapchat-9%
This is not normal
Nasko Stoychev , The battery for iPhone 6S and 7 are not compatible, different connectors, etc.. Below are links to a guide showing how to replace the battery and a link to a battery that comes with tool kit to make disassembly easier, you can also search for a battery for better pricing. You may also want to try a different charger/cable and check for dust/lint in your charge port and pick/blow it out carefully and check for any damaged pins in port or whether i is loose. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.
Yes. These iPhones have problems with the battery and you need to replace it or get it replaced. As for the 7bat in a 6 its not possible as they are different. So you need to replace the battery or get it replaced. No other way sorry, unless you just want to either get a new phone or deal with it. (I suggest getting a samsung as they are amazing and reliable phones)
For this model I wouldn't waste time replacing the battery yourself. Plug your serial number in to the link on the apple site and see if your 6s qualifies for free replacement. That way you can walk into a local apple store (or ship if there's not one nearby) and they'll give you a brand new phone.