Mergin Maps mobile app is fast evolving in recent years and we are pleased to announce a new exciting feature: Position tracking in background. It operates on both Android and iOS devices. Live tracking also works while the app is minimised in the background, increasing battery life and allowing users to do other work on the phone or with it in their pocket.
Through our users’ feedback and suggestions, we gathered a detailed set of requirements and started the work earlier this year. This feature allows users to retrace their steps and record their movement history whilst surveying. In this blog post, we'll delve into the Tracking feature in Mergin Maps and see how it can be used to monitor the survey team.
How to enable tracking
To enable tracking, you need to open your Mergin Maps project in QGIS. From the project settings, you can select the option to allow tracking for the project. Note that this will enable tracking for all users who are contributing to the project as “writer”.
To see more information, you can see the documentation page.
How to use tracking in the mobile app
Once the tracking is enabled for the project, you can start and stop tracking within the app, from the main menu at the bottom:
To stop tracking, you need to open the same menu and stop recording your tracks.
How does it work
User’s locations are saved frequently (based on the settings selected from the plugin) in the background to a GeoPackage linestring table (tracking_layer) and synchronised with the rest of the project data. The layer comes with a set of default attribute fields for the name of the user, start and end time for each track.
In addition, it records the time as M value to each vertex. The time unit is Unix epoch in seconds. To use the time you can use the QGIS expression to convert it to UTC time. The expression below converts the m values to UTC time in QGIS:
datetime_from_epoch( m*1000)
The result can be visualised in QGIS:
Customisable tracking to suit your needs
Position tracking in Mergin Maps gives you even more flexible ways to collect data. The feature will collect historic location information while it is activated on the mobile device. You have the option to set the frequency of location requests, allowing for more detailed track recording or less frequent updates to reduce power consumption and save battery. This will give you the opportunity to record routes to assets, track the position of teammates or get an idea of the time needed to travel between different locations.
We would love to hear any feedback users have about this new feature. Also, if you have any ideas about how we can make Mergin Maps even better, please visit our Wishlist where you can suggest new features like this or vote on other features you’d like to see in Mergin Maps.
Now let’s go collect some data!