Some informal testing reveals that if you’re still rocking an old iPhone, you should probably upgrade to iOS 9.2.1.

iApple Bytes put three different models of older iPhones — the 4s, 5 and 5s — up against each other in a variety of tests designed to see which of them was faster starting up, using apps and running Siri, Apple’s digital assistant. Half were running the brand-new iOS 9.2.1, which arrived yesterday, and half were still on iOS 8.4.1, which has been around since August 2015.

You can see their results below in iApple Bytes’ series of videos.

The game of jailbreak cat-and-mouse has never been quicker. Thanks to Chinese jailbreaking teams like Pangu, the slow, careful back and forth between jailbreak teams cracking open iOS, and Apple patching it, has hit breakneck speeds.

Case in point? A week after Apple released iOS 8.4.1, closing a security hole that allowed iOS 8.4 to be jailbroken, Pangu is already showing off a jailbreak solution for it.

We’re eagerly anticipating iOS 9 next month, but Apple’s got a few more fixes to give us in iOS 8.4.1, which is likely the final mobile upgrade to iOS 8.

Apple released iOS 8.4.1 to the public this morning, bringing with it a number of performance enhancements and bug fixes, plus some nice updates for Apple Music and Beats 1.

More than two weeks after seeding the next incremental beta update for iOS 8.4, Apple has made iOS 8.4.1 beta 2 available to developers.

Apple seeded two new incremental updates for developers today, one for the current version of OS X Yosemite, 10.10.5, and another for iOS 8.4.1, the current version of iOS available for consumers on iPhone and iPad.

“The OS X Yosemite 10.10.5 update improves the stability, compatibility, and security of your Mac,” writes Apple in its release notes. Further details on iOS 8.4.1 are as yet unavailable.