Collect a point
Occupy a spot and save it as a point, with a guided 30-second average on the phone or a single RTK fix from a receiver, then add details.
On this page
To record a point, stand on it and tap ⊕. The app measures your position, then asks for a name and any details. What the capture screen offers depends on your position source: the phone's own GPS, or a connected GNSS receiver.
Before you start
- An active project.
- A point type chosen as the active type. See Choose what to collect.
- A clear view of the sky. Indoors, or close to tall buildings, positions get much worse.
Capture the position
- Stand over the point and tap ⊕ on the Survey map.
- The Capture position sheet opens. It shows the type, your live latitude and longitude, and a line with the source, the fix type (with a receiver) and the reported accuracy, for example Receiver (NMEA TCP) · FIXED · ±0.013 m.
- Tap the main button:
| Your source | Main button | Other option |
|---|---|---|
| Phone GPS | Capture (30 s average) starts the guided average below. | Quick capture (single fix) takes the current fix as it is. |
| GNSS receiver | Capture takes the current fix. One RTK epoch is already survey grade. | Average multiple samples… starts the same guided average, using receiver fixes. |
The guided 30-second average
The average screen shows a countdown ring next to a plumb bubble.
- Hold the phone (or pole) upright and still. The bubble turns green when the phone is within about 4° of vertical. The text reads Keep the phone plumb and steady. If you lean further than that, it changes to Level the bubble — hold the phone upright. A phone's GNSS antenna works best held straight up.
- The heading reads Averaging position… while fixes arrive, with a running 24 SAMPLES · SPREAD ±0.010 m readout. It reads Waiting for GPS… until the first fix comes in.
- When the countdown reaches zero, the capture finishes by itself.
- Collect now (N) finishes early with the N samples you have so far. It's greyed out until at least one sample arrives.
- Cancel stops averaging and throws the samples away.
If the countdown ends before any fix has arrived, the app keeps waiting rather than inventing a position.
Fill in the form
After the capture, the form opens, titled with the type name:
- Name is pre-filled with the next free number for the type, such as Marker 4. Numbers aren't reused within a project, even after you delete one.
- Notes: free text.
- Below the name, the type's code and layer (for a Manhole, Code MH · layer V-SSWR-MHOL) show what the export will carry.
- A section named after the type holds its attribute fields, if it has any. Required fields are marked *.
- Position shows Latitude, Longitude, Elevation (MSL) (when the fix had a height), Accuracy and Samples.
- Photos: add pictures from the Camera or the Library. Tap ⓧ on a thumbnail to remove it.
Tap Save. If a required field is empty, the app asks … not filled in. Choose Save anyway to save with the field blank, or Keep editing. It warns, but never blocks.
Buried utility types get a stronger check before saving. See Open-trench utilities.
Save without details
The Save without details switch is on the capture screen. When it's on, each capture saves straight away under the suggested name (the switch shows it: Saves straight away as "Marker 4") and the form doesn't open. When it's off, it reads Opens the name, notes and photos form.
The setting is remembered and applies to lines and areas too. If a one-tap save can't be written (for example, the accuracy gate stops it), the form opens with the measurement still in hand, so you don't have to measure the point again.
If the accuracy gate stops the save
If the project has an accuracy gate turned on, the app checks each save against it. When a point fails, an alert explains why, for example 0.120 m — outside this project's 0.050 m threshold:
- Warn mode: Save anyway saves the point and marks it on the record as taken above the threshold, so the QA report can find it. Keep editing returns to the form.
- Block mode: the only choice is Keep the measurement. The point isn't saved, but the measurement and anything you typed stay on the form. Wait for a better fix and capture again, or change the rule in Tools → Accuracy gate.
Waiting for GPS, or location off
- Waiting for GPS… with a spinner means there's no usable position yet. Give it a moment outside.
- Location access is off means OpenSurvey3D doesn't have permission to use your location. Tap Open Settings to allow it, or connect a GNSS receiver instead. See Install and permissions.
Cancelling
- Back (‹) returns to the type grid without saving.
- Cancel closes the sheet. Once a position has been measured, the app asks Discard this position? and explains that the measured position and anything typed on the form go with it. Choose Discard or Keep editing.
- You can't swipe the sheet away while averaging or once a position is measured, so a long occupation can't be lost to a stray swipe. Closing the sheet in any way also stops an average that's running.
What the app records
Each point keeps a permanent record of how it was measured: the position source and fix type, the reported horizontal and vertical accuracy, the number of samples, and the time. With a receiver, it also records satellites, DOPs, correction details and antenna height. For an average, the saved position is the mean of the samples, and the accuracy is the mean of the accuracies the source reported. The spread of the samples (RMS) is kept separately. The two can differ, and the spread is what your samples actually did.