HotLap User Manual v1.2.0
A GPS lap timer and data recorder for track days, racing, karting, motorcycling and touring — on your Garmin watch.
Overview
HotLap turns your compatible Garmin watch into a motorsport lap timer. It records a standard Garmin activity (GPS, speed, heart rate, elevation, lap splits) and adds racing-specific data: live delta-to-best, G-force, per-track sectors and pit timing. You can time laps three ways — by crossing a start/finish line, by a set distance, or by tapping — and review everything afterward in Garmin Connect or export the FIT into third-party analysis tools.
HotLap is free to try (3 laps per session, unlimited sessions). A one-time Unlock PRO purchase removes the lap cap. See Free trial & PRO.
Getting started
- Install & open HotLap on your watch and step outside for a clear view of the sky so it can get a GPS fix (the outer ring blinks yellow and the status reads NO GPS until it does).
- Open the menu — tap the screen (then tap again), press-and-hold, or hold the UP/MENU button.
- Choose how laps are timed under Lap Method (Position, Distance, or Manual). See Lap methods.
- In Position mode, tell it where the line is: either Set Track (pick a real circuit from the database) or Set Start/Finish Line (drop a line at your current spot). Distance and Manual modes don't need a line.
- Start. Setting a manual line starts recording immediately; picking a track drops you back on the menu with Start Session highlighted so you can begin when ready.
Lap methods
Choose under Menu → Lap Method. It can only be changed before recording starts.
| Method | How a lap is triggered | Best for |
|---|---|---|
| Position | Crossing a start/finish line (from a selected track or a line you set). A direction check rejects wrong-way / loop-back false laps. On a database track, timing starts at your first crossing — the out-lap isn't counted. | Circuits, autocross, karting, HPDE |
| Distance | Every set distance (presets from 0.25 to 10 miles). No line needed; timing starts immediately. | Drag strips, standing miles, intervals, touring segments |
| Manual | Your first tap starts Lap 1; each tap after that marks a lap. No line, no GPS required to lap. | Anywhere a line won't work, or ad-hoc timing |
Set Start/Finish Line
In Position mode, Menu → Set Start/Finish Line drops the line at your current GPS position and immediately starts recording. Use this when you're sitting on the start/finish and there's no database track (or you want a custom line). The catch zone is sized by the Lap Radius setting.
To re-mark the line, use Reset Session (this clears the line, laps and stats), then set it again.
Set Track (circuit database)
HotLap includes a database of 2,300+ real circuits worldwide — road courses, ovals, karting and their layout / direction variants. In Position mode choose Menu → Set Track: it lists the nearest tracks by GPS (you need a fix first). Pick one and HotLap sets the start/finish line for you at the real crossing, sizes the catch zone from the track's actual line width, and loads the track's real sector boundaries and pit lane where available.
After you select a track, HotLap returns to the menu with Start Session highlighted — the track sets the line but doesn't auto-start, so you can begin when you're ready. The selected track's name appears on the Stats screen and is saved into the activity file.
Request a new track
Don't see your circuit, or spot one that needs fixing (Check Here)? Request it and it can be added in a future update. Email info@thesterk.com with:
- A Google Maps pin to the track's start/finish. In Google Maps, right-click the middle of the start/finish line (on the racing surface), then copy the coordinates or the share link, and paste it into the email.
- The track name (and the specific layout / direction if it has more than one — e.g. North, South, Short, Long, CW/CCW).
- Any sector and layout information you have — sector boundary locations, pit entry / pit exit / pit start-finish points, and the approximate track width at start/finish all help. Extra pins or a sketch are welcome; even just the name and start/finish pin is enough to get it added.
Sectors
Sectors split the lap so you can see where you're gaining or losing time.
- On a database track with sector data, HotLap uses the circuit's real sector boundaries (up to 8 sectors). Your splits line up with the track's official sectors.
- On a manual line or Distance mode, it falls back to 3 even splits by distance.
The Dashboard and Timing screens show live sector deltas versus your best; the Lap List shows every sector per lap. The theoretical best lap (sum of your fastest sectors) appears on the Timing and Stats screens.
Pit lane & pit stops
On database tracks that include pit data, HotLap detects when you enter and leave the pit lane and handles it intelligently so a pit visit doesn't corrupt your lap times:
- While you're in the pit lane, the normal start/finish trigger is suppressed, so driving past start/finish on the pit road doesn't count a phantom lap.
- The lap you pit on is tagged IN and the lap you rejoin on is tagged OUT in the Lap List; both are excluded from your best lap and best sectors.
- A live blue PIT timer shows your stop duration on the Dashboard, Simple Lap and Timing screens.
- If the track has a dedicated pit start/finish line (aligned with the real one), crossing it in the pit closes your in-lap right there and starts the out-lap — keeping lap continuity through the stop.
- Fastest and total pit time are shown on the Stats and Results screens, and the pit count, best and total pit times are saved into the activity.
Controls & gestures
| Action | What it does |
|---|---|
| Tap screen (wake, then tap again), press-and-hold, or UP/MENU button | Open the menu |
| Tap (Manual mode) | Marks a lap |
| Swipe / page up & down | Switch between screens (Dashboard, Simple Lap, Timing, Stats, Lap List, Track Map, Trip) |
| BACK | Exit — if a session is running you'll be prompted to Save & Exit, Discard & Exit, or Cancel |
Status indicators
These appear on every screen so you always know the state at a glance:
| Indicator | Meaning |
|---|---|
| NO GPS + blinking yellow ring | No GPS fix yet — wait for the sky view to clear. |
| SET LINE / SET TRACK + blinking red ring | Position mode with no line set. Set a line or pick a track to arm timing. |
| Blinking yellow AWAITING S/F / TAP TO START (lap header) | Out-lap — recording, but the lap clock is parked at 0. It starts at your first start/finish crossing (database track) or first tap (Manual). A manual line and Distance mode start timing immediately, so you won't see this. |
| Blinking yellow Reverse - Sectors OFF | You're running the track opposite its layout; sector splits are hidden (they'd be out of order). Lap times still record. See the FAQ. |
| REC + red dot (top center) | Recording. The dot blinks while paused. |
| PIT timer | You're in the pit lane; shows the live stop duration. |
| Green LAP flash / new-best alert | A lap was recorded; green means a new best. |
Screens
Page up/down to move between them. The one you land on at session start is the Session Screen setting.
Dashboard
An at-a-glance grid: current lap, sectors, speed, average, distance, G-force, lap count, temperature and battery.
Simple Lap
A big current-lap time, colored versus your best (green = ahead), a live predictive delta bar (a centered meter whose needle drifts green/right as you gain on your best and red/left as you lose, with the gap shown numerically), and your best lap.
Timing
Current lap, predicted lap, best lap, theoretical best, and live sector deltas.
Stats
Best lap, lap count, average/max speed, distance, max G / heart rate / temperature, ascent/descent, SpO2, respiration, pit best/total, and the selected track name.
Lap List
Scrollable lap history with sector splits and IN/OUT pit-lap tags.
Track Map
A live GPS trace that auto-fits and follows heading-up as you drive.
Trip
Available in Distance/Manual modes: moving time, distance, and distance/time back to your start — or remaining distance and estimated time to a Trip Target — plus ascent/descent.
Results
Shown when you finish: best lap + G for racing, or moving time + climb for touring, plus a pit summary.
All settings
Open the menu to reach these. Some only appear in the relevant mode or state (for example, Lap Radius is hidden when a database track is selected, and Lap Distance only appears in Distance mode).
| Setting | What it does |
|---|---|
| Set Start/Finish Line | (Position mode, before a line is set) Drops the start/finish line at your current position and starts recording. |
| Set Track | (Position mode, before a line is set) Pick a circuit from the database; sets the line, sectors and pit automatically. |
| Start Session / Pause / Resume | Start recording; while recording, pause or resume. |
| Activity | The activity type baked into the saved file (e.g. Motorcycling, Track Day). Set it before starting — it can't change mid-recording. |
| Lap Method | Position, Distance, or Manual (see Lap methods). Only editable before recording. |
| Lap Radius | (Position mode, manual line) Size of the catch zone around your start/finish line. Hidden when a database track is selected — those size the zone from the track's real line width. |
| Lap Distance | (Distance mode) The lap length, presets from 0.25 to 10 miles. |
| Trip Target | (Distance/Manual modes) A target distance that drives the Trip screen's remaining-distance and estimated-time readouts. |
| GNSS Mode | Which satellite systems the watch uses: Auto (device default), Max accuracy (multi-band / multi-constellation where supported — best timing precision, more battery), or Battery saver (GPS only). Applies immediately; falls back automatically where an option isn't supported. |
| Units | Speed/distance units: mph, km/h, or knots. |
| Session Screen | Which screen you land on when a session starts (Dashboard, Simple Lap, Timing, or Trip). |
| Static Rec View | A minimal "RECORDING" screen that overrides the Session Screen — for a distraction-free display. |
| Auto Rec Session | On by default. Once you're set up, HotLap begins recording automatically as soon as you're moving (about 15 mph / 24 km/h / 13 kn, held for a few seconds) — a safety net so a forgotten Start doesn't cost you a session. It needs a GPS fix, and in Position mode a selected track; Distance and Manual are always eligible. (A manual start/finish line already starts recording the moment you drop it, so this net only matters for the "picked a track, forgot Start" case.) The speed trigger is a fixed real-world speed, so it's the same whatever units you display. It fires once and re-arms after Reset Session. You can still press Start manually anytime. |
| Auto Pause | Automatically pause recording when you're stopped, and resume when moving. |
| Alert Timer | A periodic beep/vibration every N minutes (or Off) — handy as a stint reminder. |
| Lap Beep | Beep/vibrate when a lap is recorded. |
| Sounds | Master tones on, or Quiet (mutes tones but keeps vibration). |
| Strava (Generic) | Tags the saved activity with a generic sport type so it imports cleanly into Strava. |
| Force Pulse Ox | Forces the watch's onboard Pulse Ox (SpO2) sensor to sample during the session. |
| Save Session | Finalize and save the recording as a Garmin activity. |
| Reset Session | Clears the track, line, laps and stats and discards the current recording — for a fresh start. Confirmation required. |
| Unlock PRO | One-time purchase that removes the 3-lap trial cap (see below). |
| Version | Shows the installed app version. Tap it to open an info screen with the track database count, free/used memory, and the live GPS fix rate (Hz). |
Save, review & export
When you're done, open the menu and choose Save Session (or press BACK and pick Save & Exit). HotLap saves a standard Garmin activity that syncs to Garmin Connect like any other.
Export the FIT
In Garmin Connect (web), open the activity → the gear/settings menu → Export Original to download the .fit file. From there you can analyze it in third-party motorsport tools.
VBOX / Circuit Tools
A companion script, fit2vbo.py, converts a HotLap FIT into a RaceLogic VBOX .vbo for VBOX Circuit Tools — it maps GPS, speed, heading, height, heart rate and the G-force channels, embeds a start/finish gate so Circuit Tools auto-splits laps, and records the track name, pit summary and per-lap sector times in the file's comments.
Download fit2vbo.py · requires Python 3 and the fitparse package. Run it with python3 fit2vbo.py activity.fit to produce activity.vbo.
What gets recorded
Alongside the standard GPS track, speed, heart rate, temperature, elevation and lap splits, HotLap writes these custom fields into the activity for analysis:
- Per sample: lateral & longitudinal G, SpO2, respiration.
- Per lap: max lateral G, max braking G, sector times (up to 8), pit-stop time, and an in/out-lap flag.
- Per session: max & average speed, max lateral/braking/accel/combined G, max temperature, best lap, theoretical best, total ascent/descent, the selected track name, and pit count / best / total pit time.
track field in the activity — the activity's title stays your chosen activity type, but the track it was run on travels with the file.Free trial & PRO
HotLap is free to try: run as many sessions as you like, each capped at 3 recorded laps — including full use of the track database. To record unlimited laps, unlock PRO with a one-time purchase (no subscription).
How to unlock
- Open the menu (tap the screen, or hold UP).
- Scroll to the bottom, just above the Version line, and choose Unlock PRO.
- Follow the on-screen instructions. Your watch needs internet to complete the purchase — either via Wi-Fi, or with the Garmin Connect app open and paired on your phone.
Troubleshooting / FAQ
It says NO GPS and won't start.
Get outside with a clear sky view and wait for the fix. In Position mode you can't start until there's a fix, because the line needs a position. Distance and Manual can start without one, but laps/track won't work until a fix arrives.
Laps aren't triggering in Position mode.
Make sure a line is set (the SET LINE / SET TRACK prompt should be gone) and that you're crossing in the correct direction — the direction check rejects wrong-way crossings. If you set a manual line, a larger Lap Radius catches wider crossings.
My pit lane pass counted as a lap (or my in-lap looks wrong).
Pit handling only works on database tracks that include pit data. On a manual line there's no pit lane, so a pass near start/finish will register.
The lap I pitted on isn't in my best lap.
That's intentional — in-laps and out-laps are excluded from best lap and best sectors so a stop doesn't skew your bests.
How do I re-mark the start/finish?
Use Reset Session (it clears the line, laps and stats), then Set Track or Set Start/Finish Line again.
The header blinks "AWAITING S/F" and the lap timer isn't counting — is something wrong?
No — that's the out-lap. On a database track the lap clock intentionally waits for your first start/finish crossing so Lap 1 is a clean flying lap instead of a partial pit-out lap; in Manual mode it blinks TAP TO START and waits for your first tap. You're still recording the whole time (the out-lap is in your saved activity), and timing starts automatically the moment you cross the line or tap. Because a real pit exit is usually past start/finish, this can persist for most of the out-lap — that's expected. A manual line and Distance mode start immediately, so they never show it.
It started recording on its own — why?
That's Auto Rec Session (on by default). Once you've set up a session, HotLap starts recording automatically when you're moving (about 15 mph, held for a few seconds) so a forgotten Start can't cost you a run — and it lands you on the session screen so you know. If it fired when you didn't mean to record (driving to tech, repositioning the car), use Reset Session to discard and re-arm it, or turn the setting off in the menu. It needs a GPS fix and, in Position mode, a selected track.
Why do my sectors show "Reverse - Sectors OFF" on the watch?
HotLap checks the direction you cross the start/finish line against the selected track's layout. If you're running the track the opposite way, the sector splits would be out of order, so HotLap turns them off and blinks a yellow Reverse - Sectors OFF notice wherever splits normally appear — but your lap times still record normally. This is decided at your first start/finish crossing and stays set for the rest of the session. If it's unexpected, you likely selected the wrong direction of the track (for example the CW vs CCW version): use Reset Session and reselect the correct layout. If you're intentionally running the reverse direction, this is expected and you can ignore it.
What is GNSS Mode, and which should I choose?
GNSS Mode controls which satellite systems the watch uses. Auto uses your watch's default. Max accuracy enables multi-band, multi-constellation positioning where your watch supports it, for the tightest fixes and the most precise lap and sector timing — at a higher battery cost. Battery saver uses single-band GPS only. For timed track sessions, Max accuracy is recommended; for all-day use on battery, Auto or Battery saver. The setting takes effect immediately and falls back automatically on watches that don't support a given option.
My first lap shows no sector deltas.
Live sector deltas compare against your best, so HotLap needs one completed lap as a reference — the sector strip reads "--" until then and fills in from your second lap onward. (Your first lap's sector times are still recorded and appear in the Lap List.)
Which watches are supported / where are new features?
HotLap runs on a wide range of Connect IQ devices. For device support, pricing and the latest updates, check the app's Connect IQ store listing.