Apple logo could be used for notifications on future iPhones

The design of Apple devices typically consist of a clean casing with minimal blemishes or other elements to spoil the appearance. Outside of a user setting the wallpaper, or being happy with one of the Apple-selected colors at the time of purchase, the only real way to customize the appearance of an iPhone is to add an external case.

In a patent application published by the US Patent and Trademark Office on Thursday, Apple seems to be considering the possibility of giving users more options, by adding color-changing elements to the back of their devices.

The patent application for "Electronic Devices with Adjustable Decoration" effectively describes how a decorative element can be added to a casing. This could take the form of a company logo, like the famous Apple, or another piece of trim along the edge.

The decoration could consist of a transparent layer, which can include an adjustable optical component that changes how things seen through the layer appear. This can include the tint, a haze layer, a mirror layer, a thin-film interference filter using a dielectric stack, and color filters, giving a wide variety of different effects and opacities.

This decoration is connected up to control circuitry that can be adjusted by the device's operating system. For example, such a system could consist of a control in the Settings app where the user can make the rear Apple logo on an iPhone appear to be a reflective yellow color, or one that stands out more from the rest of the casing, or even blending in to hide the logo from cursory glances.

While the initial concept is to personalize elements of the device's design on the whim of the user, it could also serve more practical purposes.

The filing suggests the system could be used to communicate various events to the user, with the effects applied to the decorative element varying based on use case. For example, it could alternate between mirrored and plain states to highlight to the user there is an incoming call, if the iPhone is laid screen down on a surface.

The concept does not have to apply just to iPhones. The filing includes images of other Apple products, including MacBooks, which could offer similar capabilities with their rear Apple logos.

Apple files many patent applications on a weekly basis, but while the filings show areas of interest for Apple's research and development efforts, they do not necessarily translate into functions in a future product or service.

The idea of personalizing a device isn't new, as evidenced in other patent filings for the Apple Watch.

In January, Apple proposed a "Watch glow light band," an Apple Watch strap that includes light tubes in the design that could have their luminosity and color controlled by the wearable device, allowing for a wide variety of band colors. Apple has also mused on adding extra indicators to Apple Watch bands to give notifications without using the display, such as a user's progress to closing their rings.