iOS 17.4 has an unexpected charging benefit for iPhone 12 owners

Apple's iPhone 12 introduced wireless MagSafe charging in 2020

Apple's MagSafe first launched as a competitor to Qi charging with the iPhone 12 in 2020. Since then, a Qi2 standard has been released which is more in line with MagSafe, but Apple has continued to limit its peak charging speed.

MagSafe allows charging of up to 15W, but to date any non-Apple-certified charger has only been able to charge at 7.5W. It's confusing because Apple contributed its MagSafe technology to the Qi2 standard and the iPhone 15 range now supports that, but older iPhones do not.

Or rather, they did not. According to Macworld, the iPhone 12 can now be charged at more than the old Qi speed, after it's been updated to iOS 17.4.

Using non-MagSafe chargers, Macworld testing showed that iPhone 12 charging was faster than before, and even displayed the Qi2 icon. Tests using both Apple and non-Apple chargers demonstrate clear improvement.

Specifically, an iPhone 12 Pro Max was charged to 30% in 38 minutes with an Apple MagSafe Charger. It took an Anker Qi2 MagGi Wireless Charger 33 minutes to get it to 30%.

With a regular iPhone 12, the charging to 30 percent took around 20 minutes on either charger. In theory, a Qi2 charger should have been faster than Apple's MagSafe one based on the original Qi standard, but there are thermal considerations for longer charges, most likely impacting the speed.