# Using Mergin Maps Input

In the last tutorial we created a new Mergin Maps project in QGIS with layers for surveying trees and hedges. You'll now learn how to:

  • Open the QGIS project in Mergin Maps Input
  • Set GPS accuracy thresholds
  • Switch between layers to capture new point and linear features
  • Sync and save your data in Mergin Maps cloud

TIP

Need help navigating Mergin Maps Input? Mergin Maps Input Interface contains the overview of the functionality of the app's buttons and features.

# Opening the project on your mobile device

  1. Open Mergin Maps Input on your mobile device

  2. Open the My projects tab of the Projects page

  3. Download the trees-and-hedges project:
    download project

    The project should now be downloaded to the device:
    downloaded project

  4. Switch to the Home tab and tap the trees-and-hedges project
    open project

    The project should now be shown:
    opened project

  5. Pinch the screen to zoom in on your location. If you lose sight of your location, use the GPS button to recentre the map on your position.

# GPS accuracy

Let's try to capture some field data.

  1. Press the Record button:
    record

    You may now see a warning about GPS accuracy:
    accuracy warning

WARNING

When GPS accuracy falls below a threshold, Mergin Maps Input reports this to the user using the warning above and using the GPS traffic light dot. It's highly recommended that users set this threshold to a sensible value as described below.

Mergin Maps Input uses a traffic light system to display GPS status:
  • Green: OK - GPS accuracy within defined threshold
  • Orange: Warning - GPS accuracy outside of defined threshold
  • Red: No GPS - there's no GPS signal or the GPS is unavailable

Here's where to find the current GPS accuracy, traffic light dot and accuracy bubble:
accuracy bubble

  1. Cancel recording and open Settings:
    settings

  2. Set Accuracy threshold to a sensible value
    Typical values could range between 2m and 25m and typically depend on the accuracy of your mobile device and your use case.
    accuracy threshold

    You can get an idea of what accuracy your device is reporting by watching the traffic light change colour as you change the accuracy threshold.

# The active layer

In a moment we'll survey a tree. Surveyed features are added to the active layer. The project contains three different layers so we'll now ensure the trees layer is set as the active layer.

  1. Press the Record button:
    record

    The active layer is shown just above the button bar:
    active layer

  2. Tap the active layer and set it to trees:
    list of layers

  3. Press the Add Point button to survey a new tree.

    Notice how the form (e.g. species drop-down list) reflects how we configured the project in QGIS:
    drop down form

  4. Enter some values and Save the new point

# Editing features and the preview panel

Tapping a map feature shows its preview panel.

  1. Tap the tree you just surveyed:

    Information shown in the preview panel can be customised. We'll learn how in the next tutorial.

  2. Experiment with editing the tree's species and location using the edit button:

    The edit button can be used to edit the feature's attributes (e.g. species, condition) and even its location/geometry.

# Survey linear features

When creating the project in QGIS, we included a layer for linear features called hedges. We'll now learn how to survey lines in Mergin Maps Input.

  1. Set hedges as the active layer.

    Refer back to the active layer section if you cannot remember how to do this.

    We'll now survey a hedge feature.

  2. Use Add Point to add points along the line and Done when finished:

TIP

Drag the map to position points manually or press GPS to recentre the map on your location.

TIP

Areas can be captured in a similar way to lines if the project has editable area/polygon layers.

  1. Enter some attributes and a photo for the hedge:

When I surveyed my hedge, it was quite difficult to distinguish from the background map - it was a thin, light green line:

We will learn how to change layer styles in the next tutorial.

# Saving data to the cloud

To conclude this tutorial we will push the data we just collected back to Mergin Maps.

  1. Open the Home tab of the Projects page
  2. Press the sync button:

When the sync process has completed your data has been stored safely in the cloud.