This week Apple introduced its new iPhone lineup, including the iPhone 18 Pro series and the iPhone Duo. The devices feature the most advanced tech that Apple has ever stuffed into a smartphone. But if you’re not in the market for a new iPhone, there’s some good news: The company also announced a release date for the new iOS 27 operating system, which will run on any iPhone that can run iOS 26.
Apple says that iOS 27 will be released to the general public this Monday, September 14. Until then, there are some things you can do to help ease the upgrade and ensure that the latest software runs as smoothly as possible on your existing iPhone.
Update to iOS 26.6 or later
Apple included a new indexing optimization with the release of iOS 26.6, in preparation for iOS 27, that should save you lots of post-installation headaches. “Indexing” is the term for the process in which iOS goes through all the files on your iPhone and categorizes and tags them, so it can find the file you need quickly when you search for it later on.
Whenever a new major version of iOS comes out, it generally reindexes your entire phone—but this process can take days and is compute-intensive. So while the indexing is going on, it can sap your iPhone’s processing power and battery life—which is why you see so many claims on social media that the new operating system “slows down” your older iPhone.
Because iOS 27 has a completely new Spotlight search architecture that helps power the new Siri AI, indexing may take even longer than usual. That’s why, as noted by 9to5Mac, Apple added a background feature in iOS 26.6 that lets your iPhone start reindexing before you even install iOS 27. This means that, provided you have been running iOS 26.6 or later for a few days, your upgrade to iOS 27 should go much more smoothly.
To make sure you’re running iOS 26.6 or later, go to Settings > General > Software Update.
Back up your data to iCloud
Right before installing iOS 27, you should make sure that your iPhone is backed up to iCloud. While it’s unlikely an iOS 27 install will brick your phone or erase critical data, accidents can happen. If your iPhone is backed up to iCloud, at least you always have a copy of your data to restore if the worst occurs.
Your iPhone should back up automatically to iCloud each night when you plug it in before bed. But you can also force an iCloud backup right before downloading iOS 27, too.
To manually back up your iPhone to iCloud, go to Settings > Apple Account > iCloud> iCloud Backup and tap “Back Up Now.” Just make sure you’re on a fast Wi-Fi connection so that the backup doesn’t take forever.
Free up storage space
Depending on your iPhone model, iOS 27 may require 25GB of free space or more to install. If you don’t have that free space, you can’t download iOS 27. That’s why you should take the time now to check whether you have enough storage space and, if not, free up some space so your iPhone has room to download iOS 27.
Generally, the largest individual files on your iPhone are video games, which can be gigabytes in size, and 4K video, such as the kind you may have if you’ve downloaded any movies or series for offline viewing in streaming apps like Netflix and Disney+.
To see what data is taking up the most space on your iPhone, go to Settings > General > iPhone Storage. You can then determine which large files or apps you no longer need and delete them.
Update your apps
In preparation for any major new iOS release, most developers work diligently to update their apps so that they run as smoothly as possible on the new operating system. In many cases, developers ship these optimizations in their apps before the major iOS release, so users can have the best possible experience as soon as the new iOS update is installed.
In order to make sure your apps run without problems—and also take advantage of any newly supported iOS 27 features—it’s good practice to update your iPhone apps ahead of downloading iOS 27 (or at the very least, right after installing the new OS).
To make sure you’re using the latest version of all your apps before installing iOS 27, open the App Store app, then tap your Apple Account profile picture in the upper-right corner. Next, tap App Updates, and then update all available apps.
After prepping your iPhone for iOS 27, you should be all ready to install the new operating system as soon as Apple releases it.