There are tons of things going on under the hood of QGIS for the move from version 2 to version 3. Besides other things, we’ll have access to new versions of Qt and Python. If you are using a HiDPI screen, you should see some notable improvements in the user interface of QGIS 3.
But of course QGIS 3 is not “just” a move to updated dependencies. Like in any other release, there are many new features that we are looking forward to. This list is only a start, including tools that already landed in the developer version 2.99:
Improved geometry editing
When editing geometries, the node tool now behaves more like editing tools in webmaps: instead of double-clicking to add a new node, the tool automatically suggests a new node when the cursor hovers over a line segment.
In addition, improvements include an undo and redo panel for quick access to previous versions.
Improved Processing dialogs
Like many other parts of the QGIS user interface, Processing dialogs now prominently display the function help.
In addition, GDAL/OGR tools also show the underlying GDAL/OGR command which can be copy-pasted to use it somewhere else.
New symbols and predefined symbol groups
The default symbols have been reworked and categorized into different symbol groups. Of course, everything can be customized in the Symbol Library.
Search in layer and project properties
Both the layer properties and the project properties dialog now feature a search field in the top left corner. This nifty little addition makes it much easier to find specific settings fast.
Save images at custom sizes
Last but not least, a long awaited feature: It’s finally possible to specify the exact size and properties of images created using Project | Save as image.
Of course, we still expect many other features to arrive in 3.0. For example, one of the successful QGIS grant applications was for adding 3D support to QGIS. Additionally, there is an ongoing campaign to fund better layout and reporting functionality in QGIS print composer. Please support it if you can!