LapLine: Karting Lap Timer

Find the tenths.

LapLine is a GPS lap timer and telemetry app for karting, for rental karts and your own. It works from the first lap on the phone you already have, and a Bluetooth GPS receiver is an optional, affordable upgrade. Every lap, sector and delta comes from what the GPS measures, and when a figure needs more than your GPS can give, the app tells you instead of making one up.

LIVE TIMING
• Lap time, live delta to your best lap and a predicted lap, in big figures you can read on the move
• Sector and detail zone colours as on a race timing screen: purple for a record, green for a session best, yellow when slower
• A green flash on a new session best, a purple pass on a new track record
• The focus corner from your last session, and the time you gain through it
• A sun mode for bright days, and the screen stays on while you ride

PHONE GPS OR A RECEIVER
• Your phone's GPS is enough for lap and sector times
• Or pair a Bluetooth NMEA GPS receiver in your phone's Bluetooth settings, such as a Qstarz BL-1000GT, Dual XGPS160 or Garmin GLO 2, and pick it in Session setup for more GPS points per second
• If the receiver drops, timing carries on with the phone's GPS and switches back when it returns
• Every session shows the rate it was recorded at

TRACKS
• About 2,000 karting tracks worldwide from OpenStreetMap, already on your phone, the ones near you first
• A track that isn't listed? Just drive: your first lap draws it
• Place the start line by dragging it on the map or by standing on it, then set sectors and detail zones
• Import a track from a GPX or KML file

ANALYSIS
• The timing tower of every session: laps, sectors, gaps, Ideal lap, consistency and top speed
• The engineer reads your session and names up to three corners or straights where you can find time
• Corner by corner from 10 Hz: braking point, minimum speed, exit speed and time lost in every turn
• Your progress at every track: the record, your best lap and each sector across the season
• Analysis follows what your GPS can measure: at 1 Hz lap times are interpolated at the line, and corner details are hidden, never guessed

KARTS AND SETUP
• Your own kart with its number plate, chassis, engine and class, and the engine time since its last service
• Rental karts by their number at each track
• For your own kart, the setup of the day (tyre pressures, gearing, track condition and a note) saved with each session, and the engineer reads a change of setup against your last session on that kart and track

YOUR DATA STAYS YOURS
• No account, no cloud, no ads, no analytics
• Sessions, tracks and every GPS point live on your phone
• Export sessions as CSV or GPX, and import sessions from other apps as NMEA, GPX or CSV logs

Pure telemetry: no video and no engine sensors, only what GPS can measure. Timing runs while the app is on screen; it never tracks your location in the background.

Track data © OpenStreetMap contributors, available under the Open Database Licence.