I want to build a UWP app with gauges and some simple charts and don't want to buy a commercial product (at this stage of the project). What options are there for UWP apps?
The WinRTXamlToolkit has UWP specific builds and these could be a good starting point. They don't resemble the polished commercial alternatives but it might be helpful.
These are the NuGet packages I used for chart and gauges.
WinRTXamlToolkit.Controls.DataVisualization.UWP
WinRTXamlToolkit.Controls.Gauge.UWP
This is the underlying repo: https://github.com/xyzzer/WinRTXamlToolkit