For the two bottom security screws.
To remove the internal battery connector screw. buy iphone 4 battery locally
Check small electronics repair kiosks in local malls. For the two bottom security screws
Ensure you buy a battery specifically for the iPhone 4 . The iPhone 4S battery has a connector on the opposite side and is not compatible. buy iphone 4 battery locally
National or local battery specialty stores often carry "compatible" versions for older models. ⚠️ Critical Purchase Considerations
Since official Apple Stores typically do not service the iPhone 4 anymore, you will need to rely on independent retailers:
"New" batteries for this model are often old stock that may have degraded even while unused.