How one number changed user behaviour

At Felyx, I kept noticing the same thing: every time I walked home from the supermarket, the same scooters were still parked in the exact same spot. Day after day. My first thought? Maybe they were broken. But they weren’t. They all worked fine — they just had one thing in common: a low battery percentage.

Makes sense, right? When you’re choosing a shared scooter, you naturally pick the one with the highest battery.

So I asked the team: why weren’t we replacing those low batteries more often? The answer: we had a fixed threshold. If a battery dropped below that level, it got scheduled for replacement. If not, it stayed. Raising that threshold might have helped, but it would also mean replacing batteries that were still technically usable — wasting time, effort, and resources.

So I started looking at what we were communicating to users. The app showed battery status in three colors — green, orange, red — along with the exact percentage. But color drives behavior. Red means danger. And a percentage on its own doesn’t mean much.

Take this example: A scooter shows 7% battery, but that still gets you 15 kilometers. If your ride is only 5 kilometers, you actually have more than 100% of what you need — but “7%” looks risky, so you skip it.

We redesigned the battery display: The color coding was removed. The percentage was replaced with a clear range in kilometers. The battery icon itself became neutral black with three fill levels — visually simple, but behaviorally more accurate.

The result? Those once-ignored scooters? They started moving again.