To remove the internal battery connector screw.

National or local battery specialty stores often carry "compatible" versions for older models. ⚠️ Critical Purchase Considerations

Stores that focus on vintage electronics or legacy device repairs.

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.

If you plan to install it yourself, you will need specific tools often sold in "Fix Kits":

buy iphone 4 battery locally

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