Form and function: App sound design with Apple's Hugo Verweij
Imagine the sound of a seatbelt as it fastens. That distinctive cue is one of millions of sounds in our lives that communicates to us and makes processes easier. When it comes to apps, sound is also a core component of functionality and user experience. It can help us understand interactions better and differentiate an app's identity.
Hugo Verweij is a senior sound designer in the Human Interface team at Apple. His talk at the WWDC Apple Developer Conference makes the case for better consideration of sound. Here are some of his key lessons in sound app design.
Case study: Dark Sky app
Dark Sky delivers hyperlocalised weather information, and warns of impending rain.
Verweij praises their notification sound for its 'liquid' feel, communication, cleanness and distinctiveness.
Hugo advocates taking inspiration from real life. Record sounds that relate to your app to create an inspirational sound palette.
Your finished sounds don't have to be perfect replicas, but experimenting with these real-life sounds could provide creative direction. You don’t have to be a sound designer to do this - a phone recording will suffice.
Sound can communicate powerful emotions very fast. Always consider how you want your users to feel. Do you want to excite them, calm them, warn them…? Make sure the emotions your app sounds convey are helpful and appropriate.
Where are your users likely to be when they hear your app? What will they be doing? Make sure your sound cuts through the locational noise, whilst remaining unobtrusive. Be aware of who else might hear the app sound other than your user, and how much private information it transmits to those in the vicinity.
Consider how your sound matches your visual design. Aim to create a natural, consistent partnership between the two.
The Apple Watch sounds were inspired by the sound of striking the product's stainless steel casing.
Default notifications or generic sounds will do little to help your users or identify your brand. Distinctive sounds can differentiate notification types and potentially save your user time. They will also bring a unique personality to your product.
With app sound, less is more. Don’t overdo it - particularly with user interface sounds. Too much noise can detract from the functionality of the app. Pick your key moments, and use sound sparingly.
Always give your users to option to turn the sound off.
If you’re adding sound to haptics and animations, be precise with your timings. Even 10 milliseconds can make the difference between your sound hitting the mark or feeling ‘off’.
Pay attention to the capabilities of the speakers on the devices your app will be used on. Many devices such as smart phones have limited bass frequency capabilities, so remove these frequencies to create the cleanest sound. Test your sound on all possible devices.
Your app's sounds might be heard millions of times every day. At one point during the Super Bowl, there 360,000 texts were sent per second - that’s a lot of notifications. Listen to your sound again and again over many weeks to make sure it’s not irritating.