Advanced Editing comes to Mapit GIS
For over a decade, the answer to "I need to split this polygon" or "I need to buffer that line" has been the same: stop what you're doing, walk back to the truck, transfer the file to a laptop, and open QGIS. Not any more.
The latest Mapit GIS Android release brings a full Advanced Editing toolkit straight to the map. The four operations you used to fire up a desktop GIS for now ship in your pocket: Split, Merge, Buffer, and proper Vertex Snapping. All running on-device, fully offline, against native GeoPackage.
The four tools, in one minute
Split - cut a feature in two
Tap a polygon or polyline, open the Tools sheet, draw a single cut line across it. The line tints orange while you draw, green when the cut is valid, red if it isn't. Apply, then pick which of the two pieces keeps the original feature ID and attributes. The other becomes a new row.
Behind the scenes the geometry split is computed by JTS (Java Topology Suite), the same library QGIS uses. Inner rings (polygon holes) are handled automatically; Z values are interpolated along the cut. Read the full guide: Split Operation.
Merge - combine two adjacent features
Pick a polygon or polyline, open Tools > Merge, tap a second feature on the same layer. Mapit draws the merged shape in purple with A and B labels at each input's centroid, and you choose which side's row survives the operation. Apply, and the kept row's geometry is updated to the union while the other row is deleted, all in one atomic write.
The tool refuses to silently produce degenerate topology: disjoint polygons on a single-polygon table, bowtie corner touches, and T-junction polylines are all caught and named in plain English. Full guide: Merge Tool.
Buffer - generate a stand-off zone
Tap any feature - point, polyline, or polygon - open Tools > Buffer, and drag the slider. A live preview of the buffer renders on the map as you change the radius. Apply, and the result is inserted as a new polygon into your active polygon layer.
Common uses: a 50 m proximity zone around a monitoring well, a stand-off along a pipeline, a 10 m growth area around a parcel, or a donut ring around an existing polygon. Negative radii (inward buffers) are supported with a single setting toggle. Full guide: Buffer Tool.
Vertex Snapping - topologically clean digitising
The quiet hero of the release. Turn on Vertex Snapping and every new or dragged vertex automatically pulls onto the nearest existing vertex or edge within a radius you configure. No more hairline gaps between adjacent parcels. No more two coordinates that are nearly the same but not quite. Snapping respects all three vertex input modes (tap on map, crosshair, drag) and works across all visible layers, the active layer only, or a specific layer of your choosing.
A small orange indicator on the map confirms which target the next vertex will land on, and a circular loupe floats above your finger during a drag so you can see exactly what is in range. Snap radius and edge-snap are configurable in Snapping Settings.
Why this matters
This release is not about adding more features for the sake of a longer changelog. It's about closing the loop on a workflow that has been broken since Mapit started in 2013: collect in the field, edit in the office, sync back, repeat. That round trip cost time, risked data loss, and meant the person who collected the geometry was rarely the person who cleaned it up.
With Split, Merge, Buffer, and Snapping running natively against a GeoPackage on the device, the loop closes. You can subdivide a parcel, merge two adjacent forestry stands, buffer a hazard around an infrastructure point, or fix a topology hairline gap, all while standing on site, without a data connection, and without leaving the file you were already working on.
The result file is still a vanilla OGC GeoPackage. Open it in QGIS, ArcGIS, FME, or any other tool that speaks the standard, and every edit is there. No vendor format. No conversion step. That commitment to open standards is part of the platform story and is not changing.
Where it fits
If you've been following along since the 3.0 announcement in January, this release builds directly on the foundation that landed then: edit sessions reworked around Jetpack Compose, long-press to start editing, inner-ring support, redesigned vertex styling. Advanced Editing is the next layer on top of that foundation, and the snapping engine is already plumbed through every vertex input mode in the app.
For Mapit GIS on iOS, Advanced Editing is on the roadmap. The vertex input + snapping stack needs to land on iOS first. Same GeoPackage schema, same JTS-equivalent operations, just behind a slightly longer build queue.
Pricing
Advanced Editing and Vertex Snapping are Mapit Pro Plus features. The master toggles are visible to Free and Pro users in Settings > Advanced Editing and Settings > Snapping, so you can see what is on offer; turning them on opens the paywall.
Existing Pro Plus subscribers get the entire toolkit at no extra cost.
Try it
Update to the latest version on Google Play, open any project with a polygon or polyline feature, long-press to start editing, and look for the Tools chip on the right-hand toolbar.
If you've ever found yourself muttering "I'll fix this in QGIS later" - this release is for you. The "later" is now "now".
Mapit GIS is a professional Android and iOS GIS app used by surveyors, foresters, ecologists, utilities, and field crews worldwide. Fully offline, native GeoPackage, open standards throughout. Learn more.