OsmAnd Development plugin
OsmAnd development plugin is only necessary for developers. It allows you to simulate navigation routes, check screen rendering performance, etc.
If you need to check how the routes are built, how voice guidance works, etc, you need to go to the dashboard, find Simulate your position card and tap Start simulation. You'll be able to either build a new route by selecting Simulate using calculated route or use a GPX track for that.
To simulate a navigation route, you'll need to calculate a route first and then use this option.
If you select the GPX variant, you'll be able to pick the speed and then the track to follow.
You can set which functions of the plugin you need. To do that, please go to Settings - Plugins - OsmAnd development and select Settings. There, you'll have the choice to turn on the display of rendering information which will give you a popup with that information every time the map is being rendered, several navigation options, you'll also be able to test voice prompts. Also, you'll see the Use magnetic value option and some information that might be helpful.