New York CNN Business  — 

Remember the good old days when your phone was running out of juice and you could easily snap off the back cover, pull out the battery and swap in a new one?

Those days are long gone. But Apple (AAPL) is rumored to be developing the next best thing: a battery-boosting accessory that attaches magnetically and wirelessly charges your iPhone while you’re using it.

The iPhone maker has been working for at least a year on a battery pack that would attach to the back of iPhone 12s using MagSafe (the same tech that the new iPhones use to connect with wireless charging pads and other accessories), according to a Bloomberg report Friday citing people familiar with the matter.

Apple was planning to launch the product in the months following the iPhone 12’s October release, but faced software issues “such as the iPhone erroneously indicating that the pack is overheating,” according to the report. Sources told Bloomberg that the development challenges could cause the product’s release to be delayed or scrapped altogether.

Apple did not respond to CNN Business’ request for comment on the report, and an Apple spokesperson declined to comment to Bloomberg.

Although it feels like the future, this kind of technology has been used before. Exhibit A: the Moto Z, a modular phone from Motorola that gained little traction but featured some bold innovations. Motorola sold a thin “power pack” battery accessory that snapped onto the back of Moto Z phones using magnets, which added up to 16 hours of battery life. The phone also had other modular accessories, including a speaker and high-quality zoom camera.

Unlike the smart battery case Apple made for its iPhone X lineup, the rumored magnetic battery pack for the iPhone 12 wouldn’t serve as a “full protective case,” though some prototypes of the accessory have a rubber exterior, Bloomberg reported.

A portable battery accessory could be especially helpful for customers using the 5G service on their iPhone 12, which is expected to be a bigger battery drain than 4G LTE connectivity.

A MagSafe battery pack would join Apple’s slate of wearables and accessories, which have gained increased importance for the company as it looks to move beyond iPhones as its chief source of revenue. Apple’s wearables, home and accessories segment brought record revenue of nearly $13 billion in the quarter ended December 26 — accounting for more than 11% of the company’s total sales.