Sorta accurate. To the millisecond. Now on Android.
NSAT is a timing app for open-road time-speed-distance racing — Silver State Classic, NORC, Big Bend. It pairs with a RaceBox GPS receiver, starts the clock by itself at your assigned GPS-synchronized start time, and stops it the instant the front of your car crosses the finish line. Same timing core as the iPhone version, now running on Android.
Android 8.0 or later. The file downloads first — tap it, allow installs from your browser, and continue past the unknown-developer notice.
Live demo on compressed time — in the app, the start is your event-assigned time and there is no start button to press.
The big idea
Open-road racing is scored against time, not against other cars on the road. NSAT is built around the three facts of that format.
You set a start time, synchronized to GPS atomic time. When the satellite clock reaches it, the timer starts on its own — interpolated between GPS packets, finer than the receiver's update rate.
The finish is a coordinate, not a button press. When your position crosses the finish latitude or longitude in the course's direction of travel, the timer stops — offset so it's your nose, not your antenna.
Course distance ÷ target speed = a perfect time. Everything on screen exists to drive your variance from that time to zero at the line.
In the cockpit
Black screen, maximum brightness, thin monospaced digits — readable in desert sun. Every card below borrows its color from the instrument it describes, exactly as on the phone.
The average speed that brings variance to exactly zero at the line — live, from mile 5 until the final minute of the run.
Finished leg one 12 seconds slow? Flip one toggle and leg two paces you 12 seconds fast, so the two legs net out. Logs still score true.
Lose GPS in an underpass near the line and the app projects your last known speed to the finish — recorded, and clearly marked as estimated.
Tell it how far the antenna sits behind the front of the car (0–22 ft) and the finish threshold shifts to match. The car finishes, not the puck.
Start and finish are interpolated inside the GPS packet interval, with distance blended to the surveyed finish coordinate over the final miles.
Course, coordinates, speeds, times, variance, finish type — saved automatically, and exported as a spreadsheet file you can share or email.
Under the hood
Timing this fine takes more than reading the GPS and printing a number. Here's the path every satellite reading travels between reaching your phone and moving the clock on screen.
Readings arrive from the RaceBox 25 times a second. Each one is set aside the instant it lands, so nothing is ever waiting in line.
Every reading is verified before it counts, and time-stamped the moment it's read — not whenever the screen gets around to it.
The finish check happens right there, at the earliest possible moment, rather than waiting its turn behind the display.
Between readings the clock keeps advancing on its own, so the display runs smooth instead of ticking 25 times a second.
A run, start to finish
Connect the RaceBox and wait for race quality: full 3D fix, horizontal accuracy under one meter, nanosecond time resolved. The app won't arm until all four lights are green.
Pick the course leg, set target speed, confirm the GPS offset, decide on the variance offset — then dial in the assigned start time last, in 30-second clicks.
The GPS clock reaches the start time and the timer is running. The display reorganizes: elapsed time, live variance, distance in the title bar. Drive.
Green means ahead, red means behind. REC SPEED tells you the exact average to hold from here to arrive at zero.
The finish card goes red at one mile out. The crossing is detected on the course's axis, interpolated between packets, and corrected for the car's nose.
Final time, perfect time, variance to the millisecond, average and top speed — on screen, in the log, and in the CSV.
Getting started
Install the app, pair the receiver, and you're ready. No accounts, no sign-in, no network connection — NSAT talks only to the RaceBox in your car.
Only on Android 11 and earlier, where the operating system requires that permission before any app may scan for Bluetooth devices. NSAT never reads your phone's location — every coordinate you see comes from the RaceBox. On Android 12 and later the permission isn't requested at all.
Any timing device earns its place at the start line by proving itself first. Give it a shakedown:
iPhone vs Android
The timing is identical on both. These are the few places Android behaves differently.
| Area | iOS | Android |
|---|---|---|
| Leaving mid-run | Home button captures an emergency manual stop and exits. | Same behavior, extended to Home, recents, and app switching. |
| Permissions | Bluetooth prompt on first launch. | Bluetooth on first launch, plus Location on Android 11 and earlier — required by Android before any app can scan for Bluetooth devices. |
| Sharing the guide | Print, or send as a PDF. | Print, or send as a PDF. Run logs export as CSV on both. |
| Screen rotation | Rotates to landscape. | Stays in portrait, so a stray rotation can't disturb a run in progress. |
Documentation
The full guide — setup, the automatic start, in-run displays, the three finish types, chasing zero across legs, and troubleshooting — is embedded in the app itself (the book icon), printable and shareable from inside it, and reproduced here in full.
Read the user guide