Amazon.com: MFI-Apple Certified - ibattz Mojo Vogue Removable Battery Case for iPhone 4 and 4S White 1700mAhX2 fits all version of iPhone 4S/4 : Cell Phones & Accessories
iPhone Randomly Turns Itself Off with Battery Remaining? This May Fix it | OSXDaily
iPhone Won't Charge? Here's Why iPhone Isn't Charging & How to Fix It | OSXDaily
Amazon.com: Winnerplusa Battery for iPhone 4 (3in 1) not Compatible with 4s : Cell Phones & Accessories