While on vacation to Galveston, TX, I was using the app when I suddenly realized there was no more land. Around 80-90% of Galveston is shown to be water according to the app. I know you take your data from the OpenStreetMap data. However, their map indicates an island where your map indicates water. As for using the TomTom map, OpenStreetMap is free.
This problem is related to obsolete earth_osm (we will hopefully update it in couple months). There are several mistakes and this one is another (next to Lefkada or the island of Lewis & Harris (Scotland), some coast area in Australia, ...).