iPhone 4iPhone 4 in BlackGPUPowerVR SGX535Memory512 MB DRAMStorage8, 16, or 32 GB flash memoryBattery3.7 V, 5.3 Wh (1,420 mAh) Lithium-ion battery
Using your security screwdriver, remove the 2 screws on either side of the dock connector port.
Set them aside.
Gently slide up the back plate by applying a bit of pressure along the bottom with your thumbs and sliding upwards.
Now lift off the back plate and set it aside.
How do you take the battery out of an iPhone 4?
Remove the back plate