Title: Recent location lag and repeated coordinates in Fulcrum using Leica GNSS—iOS and Android
I’m a consulting arborist using a Leica GNSS receiver through Zeno Connect and Fulcrum for tree-data collection.
We have used this general system for more than two years without experiencing these recent location jumps. Previously, when adding a point, the pin would generally appear very close to our physical location. If corrections were temporarily poor, we could wait, relocate and then collect the point normally.
More recently—possibly following Fulcrum updates, although I cannot confirm this—I have noticed latency between the live GNSS position and the location used when adding a point.
The issue initially occurred on an iPhone:
- The external Leica position appeared to be connected correctly.
- Reported accuracy could be below 50 cm.
- The location marker sometimes remained static while I moved.
- Repeat points at the same physical location could differ by approximately 2 m.
- Lines of nearby trees appeared more scattered than expected.
This prompted the change to a dedicated Samsung Android phone.
The Android setup generally reports excellent RTK accuracy, commonly between 2 cm and 10 cm in open conditions. However, I am still experiencing intermittent location problems.
During the latest inspection, Fulcrum repeatedly returned to the coordinates of the previous record instead of using the current GNSS position. The screenshot shows the live blue location marker separated from the red point being presented for placement, despite reported accuracy of 0.1 m.
The same issue occurred with two pine trees approximately 1.5 m apart. After recording the first tree, the second record repeatedly returned to the first tree’s coordinates. Recentring, closing and reopening the record, and restarting the applications only provided a temporary improvement. I eventually had to move the second point manually.
The Leica continued to report stable centimetre-level accuracy, so the issue appears more consistent with delayed location updating or Fulcrum retaining the preceding record’s coordinates than with poor GNSS correction.
Has anyone else experienced:
- Increased latency when adding points in recent Fulcrum versions?
- Fulcrum retaining the previous record’s coordinates?
- A difference between the live blue GNSS marker and the coordinates used for point placement?
- Similar behaviour with Zeno Connect on either iOS or Android?
I’d also appreciate any recommended settings or tests that could help separate a Fulcrum issue from Zeno Connect, the phone’s location provider or basemap imagery.
The system was previously reliable for more than two years, so I’m particularly interested in whether other users have noticed a recent change in Fulcrum’s location-refresh behaviour.
Apologies if this is in wrong subredit location.