Courtesy of adsbexchange, consider contributing your data!

• Existing receiver: https://github.com/adsbexchange/adsb-exchange#ads-b-exchange-setup-scripts-airplane
• New receiver: https://www.adsbexchange.com/how-to-feed/adsbx-custom-pi-image/

1. Download the tiles (700 MB download, disk space required around 2 GB)

curl https://raw.githubusercontent.com/wiedehopf/adsb-scripts/master/osm_tiles_offline.sh | sudo bash

2. optional: Download extra detailed tiles (1.3 GB download, disk space required around 4 GB)

This doesn't work without step one.

curl https://raw.githubusercontent.com/wiedehopf/adsb-scripts/master/osm_tiles_offline_10.sh | sudo bash

Finish tar1090 integration

Even with already installed tar1090, run the install / update script for tar1090, it will autodetect the tiles installed above: https://github.com/wiedehopf/tar1090#installation

You should now have an offline map layer available using the map layer selection menu (top right of the map).