I bought a new battery kit because the one in my iPhone 5 was about to die and didn't had the money to go to the apple store and have it changed by them, they charge a lot of money for this.
I follow carefully the guide to change the iPhone 5 battery. It wasn't very hard but those small screw are so small that I had to use the screwmat to be sure I will not those little screw.
The most difficult part is to remove the old battery cause of the glue under it. Also I had a lot of difficulties to put back in place the 3 small screw in the upper right part of the iPhone, where are the camera connector... In fact one screw didn't wanted to be screw in its original place... So I just put it in place and put my iPhone 5 screen back...
So far, my phone battery last a lot longer than before. I can use my iPhone 5 for 6 hours continually and be on Facebook and play games and watch videos before the battery level drop to 20%... Before that, after 2 hours of extensive use of my iPhone, my battery was dropping from 100% to 20% and sometimes my iPhone 5 was closing when my battery had reach 19%...
I'm very please with the results. My iPhone 5 is not on warranty anymore and still have 1 year contract on it but my cellphone provider don't extend the warranty after 1 1/2 years so the last 1 1/2 years of the contract you have to pay to have your phone repair.
I was very anxious about doing it myself cause I don't have a good dexterity with my hands, I'm shaking a lot but it was very easy to do, minus that small screw who didn't wanted to be back in place again and stay there... So if I was able to do it, everyone can do it.
I change my battery 1 week ago, so far my phone close alone 1 time but I think it's not related to battery I change or dammage I did to my iPhone but it's more related to the iOS 8 major bugs...
So far I'm please with the results. Highly recommended.
Buy the magnetic mat for the screw. They are so small and easy to loose.
When you remove the screen be very carefull. It's hard to remove it and the plastic blue piece is not very solid.