Does fast charging affects battery life of iphone 8 plus???

Theoretically yes, but I wouldn’t worry about it. All charging is controlled inside the phone. It might create a little bit more heat that will reduce the longevity slightly, but when it gets closer to 100% the charging circuits back off to a lower charging rate no matter what power adapter you use.

Some here have said they’ll only use the 5w adapter that came in the box to charge overnight, but I don’t really worry. I charge using a Mac or a 12w (iPad) power adapter most of the time and I don’t see a problem with it.

Hi

No they are made to be fast charged.

Go to books download ios 11 user guide & iPhone 8 guide both are free.

Cheers

Brian 🇬-1F1E7;

Driver8666 wrote:

I use whatever is handy to charge my iPhone (including a digital cable settop box) and I've never had a problem with it. I also use one of the USB ports on my 8TB Xbox One external hard drive and it still charges. I keep the original plugs (I have 2 iPhones) in the boxes. At work, I use a Samsung charger. Still works.

I hear you. I use my Mac (2100 mA). If there was anything that bad about it, Apple would restrict the power to 1000 mA like the power adapter in the box.

I use whatever is handy to charge my iPhone (including a digital cable settop box) and I've never had a problem with it. I also use one of the USB ports on my 8TB Xbox One external hard drive and it still charges. I keep the original plugs (I have 2 iPhones) in the boxes. At work, I use a Samsung charger. Still works.