Help

Guide & FAQ

Learn how to download log files, read your results, and trim, merge, or compare sessions. Find answers to common questions below.

Quick start Feature guide FAQ Contact support
Quick start

Get started and find your best run in six steps

Use the same workflow for logs downloaded over WiFi from an ESPc Logger and files imported from other devices.

Install from the App Store on iOS or Google Play on Android, or open the web app in your browser.

Download on theApp Store Available onGoogle Play Use in your browser Open web app ↗

Turn on your ESPc Logger: the app finds it over WiFi and shows it under the tabs with its new files, ready to download — or import .sbp, .ubx, .oao, .gpy, .gpx or .fit files from Files or another app's share sheet.

Open a file to see its sessions. Sessions are detected automatically when the file is analyzed, with no manual splitting.

Your phone calculates speed results for 2 s, 10 s, 30 min, 1 h, sprint distances, the nautical mile, and alpha 500.

Open a session and choose Trim to cut the paddle-out, a shore break or a GPS gap. Select two or more sessions and choose Compare to line them up, or Merge to combine them into one continuous session. Trims and merges can be undone.

Group sessions from different devices or days into an Activity to find the best run across the group. Export a session’s log file to save or share it.

Feature guide

What each part of the app does

A closer look at what you can do in each view.

Loggers & WiFi

The app can download logs directly from an ESPc Logger over WiFi. Connect to the same network, open the logger from the app and choose the files to download. For other devices, import a supported log file from Files.

WiFi modes, device settings and firmware updates are covered in the ESPc Logger guide.

Import & file formats

The Files tab holds everything you've downloaded or imported. Use the share sheet or file picker to bring in logs from Locosys, u-blox-based loggers, Motion, OpenGNSS, Garmin / COROS, or a plain GPX export.

Supported formats: .sbp · .ubx · .oao · .gpy · .gpx · .fit. Doppler speed is read straight from the file wherever the format provides it.

Sessions

A session is one continuous run, split out automatically from a file by time and location gaps — by default a break of more than 30 minutes starts a new session.

The session list shows a track preview, max speed and key intervals for each run. Sort by date, location, distance or any speed metric.

Metrics & analysis

Opening a session analyzes it on your phone: 2 s peak average, 10 s average, ½ hour, 1 hour, 100 m / 250 m / 500 m, nautical mile, alpha 500 and max speed, plus a map and speed-over-time graph.

High-rate logs are read at up to 20 Hz. Everything is computed on-device, so results appear immediately after import — nothing is uploaded to see your own numbers.

Trim, merge & compare

Open a session and choose Trim to adjust its start and end on the map and speed graph. Reset the range at any time; the original log stays unchanged.

Select two or more sessions to Compare their results or Merge compatible recordings. Deleting a merged session restores the originals. See the session FAQ for merge requirements and more examples.

Activities

An Activity gathers sessions that belong to the same outing — logged on two devices, or split across several files — into one group you manage together. GPS Analyzer can auto-cluster sessions that look like they belong together and suggest the grouping for you.

Inside an Activity, GPS Analyzer highlights the best run across the whole group. You don't need one just to compare or merge two sessions, though — Compare and Merge (above) work directly from the Sessions list on any sessions you select.

A session on GP3S

The app doesn't send sessions to GPS-Speedsurfing (GP3S). Export the session's log file (Export → Save or share) and upload it on gps-speedsurfing.com yourself.

The app computes its numbers the way GP3S does, so GP3S shows the same results for that file as you see in the app.

Export & share

Export a session's original log file at any time through the share sheet — to back it up, send it to someone else, or open it in another tool.

Settings

Timezone (device local, UTC, or a custom offset), speed units (km/h or knots), map layout and font size all live in Settings.

You'll also find Rebuild index under Maintenance — safe to use if the browse list ever looks out of sync with what's on disk — and Contact support under Support.

FAQ

Frequently asked questions

Still stuck after reading these? Jump to Contact support below.

Getting started

Is GPS Analyzer free?
Yes, the app is free to use. Download it from the App Store for iOS or Google Play for Android, or open the web app in your browser.
Do I need an ESPc Logger to use it?
No. The app has direct WiFi support for the ESPc Logger (discovery, download, configuration, OTA firmware), but it can open and analyze log files from almost any speed-GPS through the file picker or share sheet.
What file formats can I open?
.sbp (Locosys), .ubx (u-blox), .oao (Motion), .gpy (OpenGNSS), .gpx, and .fit (Garmin / COROS).

Loggers & WiFi

How do I connect to my logger?
It depends on the logger's WiFi mode. In AP mode, join the logger's own WiFi network from your phone's WiFi settings, then open the app. In station mode, put your phone on the same WiFi network as the logger — it's found automatically and shows up under the tabs. If it doesn't, add it by IP address: the logger icon in the top bar → Add logger.
The app cannot find my logger. What should I check?
Check that the logger is powered on. In AP mode, connect your phone to the logger’s own WiFi network. In station mode, both devices must be on the same network. Guest networks or client isolation can block discovery. If needed, add the logger by IP address.
Can I update my logger's firmware from the app?
Yes — from a connected device's screen you can flash new firmware over the air, no cables or desktop tool needed.

Sessions, trim & merge

How are sessions detected?
Automatically, from time and location boundaries in the log — by default a gap of more than 30 minutes starts a new session. If the auto-split doesn't match what actually happened on the water, you can fix it: select the sessions in the list and choose Merge to combine them back into one, trim a session's edges, or do both — all of it is undoable.
Do the numbers match GP3S exactly?
Yes. The on-device analysis mirrors the GPS-Speedsurfing scoring engine, so what you see in the app is what GP3S shows for the same file.
Can I remove the paddle-out or the drive home from a session?
Yes — open the session and choose Trim, then drag the start/end handles on the track and speed graph. The classic case: you forgot to stop the logger, drove home with it still running, and now it looks like you set a new top-speed record — trim cuts that tail off and recomputes every metric for the new window.
Can I undo a trim?
Yes — trimming keeps the original full range, so you can reset a session back to it at any time.
Can I combine two sessions into one, or compare them without an Activity?
Yes — select two or more sessions in the Sessions list and choose Compare to view them side by side, or Merge to combine them into one continuous session. Merge is mainly meant for sessions from the same device — one outing split into two by a gap — but it works on any sessions that meet the requirements (same location, within 24 hours of each other, no time overlap), even across devices. It's non-destructive too: delete the merged session and the originals reappear automatically.

Activities & sharing

What's an Activity, and when should I use one?
An Activity groups sessions from different devices or days together and highlights the best run across the whole group — useful when the same outing was logged twice. You don't need one just to compare or merge two sessions, though: Compare and Merge work directly from the Sessions list on any sessions you select.
Can I send a session to GP3S from the app?
Not directly. Export the session's log file (Export → Save or share) and upload it on gps-speedsurfing.com — the numbers there match what the app shows.
Can I export or back up a session?
Yes — export a session's original log file through the share sheet at any time, to back it up, send it to someone else, or open it elsewhere.

Privacy & support

Does any of my data leave my phone?
Analysis runs on your device, and without an account your logs and activities stay there. They leave it only when you choose: when you sign in to a GPS Analyzer account (your logs and records are then synced to our server, for backup, your other devices and the web app), share a session, or export/share a file. Viewing a map downloads map images from our map server (from CARTO only when ours cannot be reached), and to name where a session took place the app sends its start point to our server, which does not keep it.
What speed unit does it use?
km/h by default; switch to knots in Settings → Display at any time.
How do I get help or report a bug?
In the app, go to Settings → Contact support — it opens an email prefilled with your app version and platform. See Contact support below for the direct email address.
Contact

Still need a hand?

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Contact support

The fastest way: in the app, open Settings → Contact support — it opens an email with your app version and platform already filled in. You can also reach us directly at info@majasa.ee.