Last week I found I finally failed to stand my laggy home button, however, it's really costly to get it repaired since it has been out of the warranty now. So, I made a terrible decision, I'm going to change it all by myself. Well, the result turned out pretty fine, it works perfect now. Considered to the launch time of the iPhone 4, I think quite some users should have the same problems like me, so I am going to share the tutorial to all of you. Here we go.
Step 1 — Rear Panel
Apple has recently substituted the two Phillips screws with 5-Point "Pentalobe" screws. If your iPhone 4 has 5-Point "Pentalobe" screws instead of Phillips, please refer to the second picture.
Remove the two 3.6 mm Pentalobe screws next to the dock connector.
During reassembly, we recommend you replace the 5-point screws with equivalent Phillips screws. Our Liberation Kit provides the tools and screws needed to replace the Pentalobe screws with Phillips screws.
The 5-Point Screwdriver should only be used once, as it has the potential to strip the screws.
Push the rear panel toward the top edge of the iPhone.
The panel will move about 2 mm.
Lift the rear panel away from the iPhone.
Step 4 — Battery
Remove the single 2.5 mm Phillips screw securing the battery connector to the logic board.
Some devices may have two screws, one of which holds down the contact pad which is located above the screw indicated in red in the photo.
Use an iPod opening tool to carefully pry the battery connector up from the ends closest to the top and bottom edges of the iPhone.
Do not pry against the contact clip.
Remove the contact clip from the iPhone.