Designing touch controls for a kart racing game

Role UX Designer
Client Sumo Digital
Timeline Aug 2023 - Jun 2024
Platform iOS & Android

Background

A PC racing game needed its controls rebuilt from scratch for mobile

Stampede: Racing Royale is a live service, 60-player kart racing game. When porting it to mobile, one of the highest-priority tasks was translating the gamepad and keyboard controls to a touchscreen without losing the feel of the game.

I led the UX design for mobile controls, working alongside a game designer.

PC version of HUD

Stampede: Racing Royale PC gameplay

Research

Every top mobile kart game offered more than one way to steer

We conducted a competitor analysis of the top mobile kart racing games, documenting their features, strengths, and weaknesses. Two patterns emerged consistently across the market:

  • All games used auto acceleration, removing one control variable entirely
  • The vast majority offered two or more control presets, letting players choose how they steer

This pointed to a clear direction: rather than designing one universal control scheme, we should design two presets and let players decide. We named them Classic (one-handed steering) and Refined (two-handed steering).

Controls competitor analysis matrix

Competitor analysis matrix

Design

Two presets, playtested with 20 participants

We wireframed both presets and worked with the UI and engineering teams to get them prototyped for usability testing. We invited 20 external participants to race with both control schemes and score steering, drifting, and power-up usage from 1 to 5.

Preferences were evenly split between presets, but both scored poorly enough to require iteration. The feedback was specific:

  • Controls were overly sensitive
  • Some buttons were too small to hit reliably
  • Buttons positioned along the thumb curve blocked too much of the screen

We moved buttons to the screen edges, reduced HUD complexity in Refined by turning the whole half-screen into a tap zone, and increased touch target sizes across both presets.

Classic control scheme wireframes

Classic controls iteration

Refined control scheme wireframes

Refined controls iteration

Outcome

Iterated designs validated by further rounds of user testing

A second round of playtests confirmed the changes landed. Participants noted that the larger touch targets and repositioned buttons were significantly easier to use under pressure, and improved icon readability reduced errors on power-ups and drifting.

The two-preset model also held up. Users valued the ability to choose the scheme that matched how they wanted to play, rather than being forced to adapt to a single layout.

Although the mobile version was ultimately deprioritised before release, key design patterns were carried through to the final PC version which shipped in 2024.

Classic control scheme final design

Classic controls — final design

Refined control scheme final design

Refined controls — final design

Next project

Defining core UX systems for a competitive live service game