How to make iPhone 4 last as long as possible?

In December 2010 of my 8th grade, my grandfather, who I was very close to gave me a brand new iPhone 4. He gave it to me on the day he died.

Because of this, I love my iPhone and wouldn't trade it for anything else. To me, it represents the love between us two.

Now that I will be entering my junior year in highschool, my iPhone is about 2.5 years old. I have a solid plastic Speck case, and a very protective mirror screen protector.

My battery life is fine, but definitely much worse than I it orginally was. I have no scratches or fingerprints on the screen, and the body of the phone looks very slightly used.

My goal is to be able to keep my iPhone functioning through at least my senior year in high school.

Can somebody give me a solid list of things I can do to make my iphone last as long as possible? Again, I don't want a list of things to keep my battery functioning. I want a list of things to keep my iPhone usable instead.

This question is lovely. It's so nice that you want to be close to the item your late grandfather gave you. I'm sorry for your loss.

I too have an iphone 4, and I've had it for 2.5 years also.

I purchased a 'Life-Proof case'

now.a life-proof case will protect your iphone all over, screen, back, camera, buttons etc.

wearing the life-proof case will also make your phone waterproof. (I suggest eBay)

Iphone battery lives are known to be strong and keep charged a lot and you'll be fine.

So I suggest the above^ to keep your phone safe.

Turn down screen brightness and turn off Wi-Fi.

I respect your feeling. It is really nice to have that kind of feeling that you want to keep that phone for more years. Do not worry about it. Just be careful with the case, stickers, and over charging. Do not over charge your phone, which will damage your battery very soon. And if you want that phone to look new be careful with the case. So I'm suggesting one link which will help you to find the best case. Hope you like my suggestion.