In previous years, iOS previews were usually limited to paid application developers who took part in Apple’s developer program. Conversely, this is the second year in a row OS X has seen a public beta, with OS X 10.10 Yosemite also undergoing a public preview prior to release.

This time around, anyone with a compatible iOS device or Mac computer can sign up to try out the public preview program on Apple’s beta program website. However, despite the company’s new open-natured approach to beta testing, the preview is far from perfect and therefore isn’t meant for everyone.

The beta program, as the name implies, consists of software that’s far from finished. Both iOS 9 and OS X 10.11 El Capitan are set for an official public release later this fall, after the beta period has ended.

During the lengthy installation process, Apple continually reminds testers to save backups to avoid losing data. I can attest through my own experiences with both iOS and OS X previews that Apple’s warnings aren’t exaggerated. Bits and bytes of code—the stuff core applications rely on to run—are constantly in flux during the beta period, and sometimes seemingly minor changes made by Apple have unintended consequences on other parts of the operating system. In some cases, Apple even breaks codes on purpose with plans to fix problems in a future update.

Should users decide to install either preview be prepared to spend a lot of valuable time troubleshooting issues. Problems like saving files, launching apps, or other oddities are often common in such previews. The end result is either waiting for an update to the preview, or rolling back the entire system to a more stable OS, neither of which are ideal. Although, if you’re doing your part, users will also report any issues to Apple through a built-in feedback application, complete with a solution (if you’ve discovered one).

Apple’s new preview rules follow similar moves from other companies that run beta programs, such as Google’s Android preview and Microsoft’s Insider Program for Windows 10.

For those who are unsure about downloading the program my two-cents is to simply wait. Wait for the official OS release, or if you absolutely have to check out the new operating system make sure not to load it onto your main device(s). Remember that spare iPhone you keep stashed in your junk drawer? Now’s the time to dust it off and give it a whirl.

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