OsmAnd Navigation "Black Mask" Plugin Development

I'm looking for an experienced OsmAnd app developer to create a small plugin for the OsmAnd Navigation app. The plugin will overlay a black image/area over either the map layer or the app's overall layout, leaving a visible rectangular area around the middle of the screen where the current GPS position defaults (see attached image). The rectangular cutout area should stay centered and not move if the user pans the maps. A small button on the bottom left corner of the rectangular cutout area can toggle the mask on and off. The idea is to minimize the amount of information displayed on the screen down to a small rectangular area.

Key Requirements:
- The visible rectangle should be approximately 35mm horizontally x 45mm vertically.
- The plugin must work on iPhone.
- I am not interested in a separate app. This has to be done either through an OsmAnd plugin or if possible within a map style (*.render.xml file).I have already create a custom map style for displaying the roads in white and the rest in black (see attached image). I can provide the map style for testing. In the profile you can assume that most of the default buttons under "Configure Screen" are not visible.

Ideal Skills:
- Proficient in OsmAnd development with a strong understanding of creating plugins for OsmAnd app.
- Prior experience with OsmAnd is a plus.

Please include any relevant examples of your work in your proposal.