Zettle Terminal by PayPal is a touchscreen payment device used by merchants across the globe. Every interaction has a sound. We designed it.

The brief had two objectives: utility and brand. The sounds needed to tell merchants and customers exactly what is happening, a payment confirmed, a card declined, a session locked, without anyone needing to read the screen.
And they needed to feel like Zettle: confident, clean, and distinctly not generic.
Working with the Zettle product team, we mapped twelve interactions where sound carried real functional weight. Some replace screen feedback entirely. Others reinforce it. All of them are heard in noisy retail environments, dozens of times a day, by people with their hands full.

We use Soundbricks, our proprietary UX sound design tool, to map the semantic logic of each sound before a note is composed. Locking, unlocking, payment confirmed, payment cancelled: each interaction has a distinct function, a distinct feel, and a place in the system as a whole.