If you browse the sim racing overlay ecosystem, you quickly notice a pattern: tools trying to turn your monitor into an aircraft cockpit. Animated tachometers, rotating dials, tyre carcass temperatures carried out to single decimal places, and dense tables of sector times crammed into every corner of the screen.
They look impressive in screenshots. Then you jump into a race, dive into Turn 1 alongside three other GT3 cars at 240 km/h, and realize you cannot read any of it without missing your braking marker. By lap three, most drivers hit the hotkey and turn the overlay off entirely.
When designing APEX, we worked from a simple rule: if an element does not help you make a faster, safer decision in a fraction of a second, it does not belong in front of your eyes.
Designing for quick glances
In real motorsport and high-level virtual racing alike, peripheral vision is precious. Your eyes need to stay locked onto apex kerbs, braking boards, and radar markers. The moment you pull your focal point away from the track to decipher numbers, your lap time suffers.
Drivers do not read overlays while driving; they glance at them. That distinction guided our visual priorities:
- Color before numbers: A delta time of
-0.24sis helpful, but a subtle green peripheral glow tells your brain you are up on your reference lap before you even read the digits. - Status over raw values: You do not need to know your front-right tyre is at 84.7°C mid-corner. You only need to know whether the tyre is in its working window or starting to slide.
- Contextual appearance: Pit stop strategies and fuel calculations only matter when the pit window opens or fuel runs low. During a green-flag stint, they should stay hidden.
What we cut
Good cockpit design is mostly about having the discipline to delete things. During APEX development, we threw out dozens of concepts that looked clean in design mockups:
- Live trace graphs: Pedal input curves and slip angles belong on a secondary monitor or in telemetry review after the session. Floating over your windscreen while defending a chicane, they are pure noise.
- Card frames and shadows: Opaque boxes and heavy drop shadows cover up asphalt and apex kerbs. We switched to clean, semi-transparent contrasting surfaces with borderless text.
- Sliding animations: Smooth panel transitions look slick on the web. In the cockpit, any unexpected motion in your peripheral vision makes your brain react as if another car just lunged into your blind spot. In APEX, states change instantly.
Protecting frame pacing
Visual ergonomics only matter if the overlay performs cleanly. Sim racers spend serious money on high-refresh displays and direct-drive wheelbases. If a background tool causes even a 2-millisecond frame hitch at turn-in, the driver feels it through their hands immediately.
We built APEX to run completely isolated from the simulator's render thread. By pulling telemetry out-of-process through OS shared memory (the same pipeline we covered in our note on building one telemetry stack across five sims) and handling sync quietly via our cloud sync pipeline, APEX draws cleanly without touching the simulator's internal tick rate.
Software that gets out of the way
The best companion software gives you clarity when you need it and fades into the background when you don't. We built APEX because we wanted an overlay we would never feel tempted to switch off in the middle of a 24-hour endurance race.
If you want to see how APEX feels on your rig, join our waitlist and follow along as we approach release.
