I was busy creating a mobile App for interfacing with our map generation server. Map tiles are prerendered on a webserver. Base for the tiles is open street map. The map data is colored in a specific way that makes use of the colors available in the dispaly.
To get a map exerpt that contains the area you want to hike in, is quite easy. You plan a route of your hike with an app like Komoot or on gpx.studio. After that you can upload the gpx trail to the map rendering server. Or you can use the app to do the uploading for you. It also tracks the progress of the data generation.
After the data generation is finished the app will let you download a zip file with all the files needed on the SD card. The link to the zip file can also be shared to your pc to download it. The next big change will be to have the IndiaNavi to download the map files directly. For this reason we have that huge ID tag. It coresponds to the ID the device gives Itself based on the ESP32 Chip MAC and a Device Name that is customizable.
You can chack out the app in the Play Store: https://play.google.com/store/apps/details?id=tech.platinenmacher.navi