Apple releases iOS 11.3, the biggest update for iPhones since iOS 11 first launched

Today, Apple released iOS 11.3 to all supported devices, including the iPad Air and later, the iPad mini 2 and later, the iPhone 5S and later, and the sixth-generation iPod touch. The update is available for download now in supported regions.

With several new features, it's arguably the biggest update to iOS since iOS 11 first released. iOS 11.3 addresses battery-based performance throttling on older devices, adds significant new capabilities for augmented reality, adds the ability to chat with customer support reps from companies in Messages, and lets users access their personal health records in the Health app.

Apple also released smaller updates for tvOS (tvOS 11.3) on the Apple TV and watchOS (watchOS 4.3), as well as macOS High Sierra 10.13.4, which adds eGPU support and Business Chat to Macs. Let's dive into what each of these updates adds for users.

Battery Health

As promised, Apple has made it possible to disable performance throttling on older iPhones whose batteries have degraded to the point that they pose a risk for unexpected shutdowns resulting from voltage shortages. Apple lists this as a beta feature.

There is now a section in the Settings app, nested under "Battery," called "Battery Health." If you visit this on a phone with a battery Apple deems healthy, it will simply serve up brief copy explaining some key concerns with iPhone batteries, along with a link to a webpage that goes into more detail. It will also show a value for "maximum capacity." This value is a percentage.

Apple explains it this way:

This is a measure of battery capacity relative to when it was new. Lower capacity may result in fewer hours of usage between charges.

There's a section of this settings screen labeled "Peak Performance Capacity." If your phone has never experienced an unexpected shutdown due to low battery health, it will simply say: "Your battery is currently supporting normal peak performance." However, if your battery has dropped to a low enough maximum capacity, you'll be shown this copy instead:

This iPhone has experienced an unexpected shutdown because the battery was unable to deliver the necessary peak power. Performance management has been applied to help prevent this from happening again.

Next to this, you'll see an option to disable the performance-management feature that has so irked iPhone owners. It also tells you that you can upgrade the battery to solve this problem completely:

Your battery's health is significantly degraded. An Apple Authorized Service Provider can replace the battery to restore full performance and capacity.

Notably, performance management is disabled until the phone first experiences an unexpected shutdown; it's not activated simply by a maximum capacity below a certain value, and you can't turn it on unless you've run into the problem.

The note about the Apple Authorized Service Provider is meant to address a consumer complaint that Apple was not transparent with users about the option to upgrade the battery—that complaint is key in the class-action lawsuits that have popped up in response to the performance management controversy that began last December when Reddit users and the dev behind benchmarking app Geekbench confirmed that iOS throttled performance on devices with underperforming batteries.

Apple does not offer this feature on iPads, but this update does add a new iPad feature called "charge management." The update notes say it "maintains battery health when iPad is connected to power for prolonged periods of time, such as when it is used in kiosks, point-of-sale systems, or stored in charging carts."

ARKit 1.5

ARKit is Apple's augmented reality application programming interface. Apple introduced ARKit at its Worldwide Developers Conference (WWDC) last year. The framework handles some of the lower-level heavy lifting for augmented reality so developers can focus on customization of its experiences and on content.

Previously, ARKit could only accurately place objects on flat, horizontal planes, limiting the range of applications developers could make. With ARKit 1.5, developers can now place objects on vertical planes like walls, and accuracy is improved when mapping objects onto surfaces that aren't completely flat.

It also adds image-recognition capabilities. For example, an AR app could show a full-sized robot if a poster for an associated robot movie is seen by the phone's camera, or it could provide additional context in a museum when a certain painting is seen. Apple touts a "higher-resolution real-world camera view when using AR experiences," and auto-focus is now supported in AR views as well.

AR is a major focus for Apple this year; it has been the subject of many of the company's top executives' comments about their strategy and new initiatives, and many of the major additions and updates in the iPhone 8, iPhone 8 Plus, and iPhone X—all released late last year—were focused on laying the ground work for improved AR experiences, either with new sensors or improved performance.

Tim Cook has said he believes AR will be a watershed moment for the app store once AR developers find their stride. App intelligence firm Sensor Tower recently estimated that apps built on ARKit have been downloaded 13 million times since iOS 11's initial release. Half of those apps are games, but Pokémon Go and several other popular AR apps are not included in those numbers because, for all or some of the reported period, they were not built on ARKit.

New Animojis

This update also adds four new Animoji for the iPhone X: a skeleton, a lion, a dragon, and a bear—not to be confused with the existing panda bear Animoji. They're pictured below. These new Animoji don't add any new functionality; they're just new skins for the TrueDepth sensor-based, iPhone X-exclusive feature.