Tips on how to keep your iPhone battery healthy?

I got sprint contract for 2 years, I have insurance for 2 years and then I can sell it back and get the iPhone 7 or sumthing but how can I keep the battery healthy and it will last the while day like it does now. Tips please: D

Added (1). Its iPhone 5

Would you find this kind of annoying too?

So I have this group chat on my iPhone with 4 of my best friends. Almost everyday, one of them, let's call her Cynthia, doesn't always follow what's happening. So we would all be having a conversation and I would say something and she would just respond "Wait what" or "what" and UGH it gets me so annoyed i don't know why. It makes me feel almost stupid and a little embarrassed bc then I need to explain my simple text to her. A lot of times I don't see what's confusing about the texts, and no one else does, but she always has to say "what." And the worst part is she doesn't use a question mark so it sounds almost sassy. It's not just me but I haven't really kept track of her doing it to other people. It happens a lot just in texts between us two, also. I would pour my heart out to her or say something, ANYTHING, and all she replies is "wait what."

Do you see how I'm kind of annoyed? She just did it like 10 minutes ago and I literally felt anger in the pit of my stomach. I get she might not understand what I'm saying but she could easily just say "what do you mean?" or "wait can you explain that again?" ANYTHING but the "What". I just find it rude. What should I do next time she says it? Today I ignored it but one time I said "what was even remotely confusing about what I just said"

Iphone screen turned black all of a sudden?

I was on my iphone a few minutes eariler and it suddenly turned off. The battery was at 40%. I tried to put the iphone in dfu mode ( lock + home button for 10 secs) but its still didn't turn on. Not even the apple logo showed up. I tried connecting it to my computer but it says unrecognized device.

My iPhone 4 music won't work?

With headphones in sometimes the sound just stops but the song is still going I just can't here it. It starts working if you pull the head phones out and push them in again. How can I make it work

How to download winter board for my iPhone 4?

I have an up to date iPhone 4 and I was trying to find a way to download custom sliders. I tried downloading it but it said that safari could not download file. I have tried multiple sites and none have worked. I really just want the custom sliders. Does anyone know what to do?

How to make group message work between a galaxy s4 and iphones?

Me and my friends used to group message with our iPhones everyday but then my phone turned off and never turned back on, basically what I'm saying is it broke. Well then I got a galaxy s4 and I haven't been able to group message them since. I've Already heard that i'm supposed to go into my old iPhone and turn off imesage but I don't understand what that'd do to help, plus I'm literally not able to do that. Is there anyway to go into settings to make it work or is there an app I can use that will definitely work?