With the lack of a physical home button of any kind with iPhone X, Apple has a new interaction metaphor: the home indicator. This is the thin bar that sits at the bottom of the iPhone screen.
At first glance, it might seem like an annoying blemish on the edge-to-edge design. But just like the notch at the top of the phone, the home indicator plays an important role.
The presence of some UI, even something as inert and discreet as a pillbox bar, provides important context on how people use the phone. A common criticism of the iPhone X in the reviews is that it takes time to learn all the new gestures.
The home indicator helps to establish the basic, most fundamental, interaction model of the device. How to go home. Right from the lock screen, Apple teaches users that they have to swipe on that bar to navigate around the interface.
Even if you’ve never heard of an iPhone X before, you can pick up one and the OS guides you through. If you tap or push on the lock screen in the wrong way, iOS will animate the home indicator – softly pushing it upward – to shadow what action needs to be performed.
If you wait even longer, instructional text appears: ‘Swipe up to unlock’. It’s a tutorial from the first instant. And if you know what you are doing, you will never see the prompt again.
When you get to the home screen and into an app, you have already been trained to swipe up on that bar to go back. Activating multitasking uses the home indicator as a foundation, and the swipe-and-hold is a natural extension of the app closing gesture. This is not intuitive per se, but it doesn’t really need to be. The fundamental feature of the iPhone UI is getting back to the home screen, and Apple makes that action easy to learn and very efficient.
The home indicator’s permanent presence on screen is a visual cue of where to swipe and allows the system to receive touch inputs faster, and start the swipe gesture more quickly than if the home indicator wasn’t there. iOS doesn’t have to worry about potentially cancelling a gesture meant for the open application. This is a big factor why the new iPhone X multitasking feels so much more responsive than, say, opening Control Center on an older iPhone.
When you switch your phone to landscape, the home indicator moves too so you can always orient yourself around it and know where to swipe. This is especially important in apps like Camera, which rotate UI elements when the device moves from portrait to landscape but the actual app does not move, so the dismiss gestures still have to be started from the same place. The home indicator therefore also doesn’t move.
Without the indicator as a visual aid, you might accidentally try swiping to dismiss Camera from the wrong edge.
Developers can request to the system to enable an auto-hiding feature for the home indicator. This is used in video apps for a distraction-free viewing experience, but it is meant to be used very sparingly. The system retains the final say, so it can go against the wishes of the app and still present the home indicator if it deems it necessary.
I’ve seen a few suggestions bandied around that Apple should add a ‘power user’ toggle to the OS which would mean the home indicator is never displayed. I don’t think this has much value as the visual guide is needed for situations like portrait and landscape, and the physical space onscreen could not be reclaimed by app content anyway. Apple would still need to reserve screen space for its gestures even if the bar wasn’t visible.
A cool detail about the home indicator is that it dynamically tints itself to complement the surrounding application interface. When shown on light interfaces, the indicator is a gray/black colour. When shown on dark UI, it is white.
If you look closer, it isn’t necessarily a simple flat colour. It is actually a luminosity blend of what content it is occluding. This effect is subtle, but is a nice touch which adds a little extra contrast (and probably helps avoid OLED burn-in as well).
My one big complaint with the current iteration of this system is that the automatic tinting is not perfect. Apple does not give developers the ability to suggest a preferred color for the indicator; the system has to work one out on its own.
Whilst it does a good job most of the time, there are a couple cases I have noticed where it is too distracting. Take the iTunes Store movie section for example (screenshot above). This is a dark interface with dark controls and gray text. iPhone X determines the home indicator should be 100% white in this scenario.
This is not ideal. The stark white rounded rectangle is a jarring imposition on this toned-back interface of blacks and dark grey. The iPhone X’s high-contrast OLED display only exacerbates this effect. I mocked up a comparison of a better color palette choice:
In this example, I colour-matched the indicator to the tab bar text colors. It makes it fit in without being invisible; it still provides the suggestion of an available gesture area without distracting the eye like it does now with the white one.
This is fine tuning that Apple is no doubt already aware of and will be lining up possible solutions for future iOS releases. In general, I think they’ve done a really good job pushing iOS into a new direction (sans physical navigation) and it all starts with the home indicator.