Importing, exporting and converting file formats is the inverse of easy. I came across this thread searching for a solution. As a freeplane user on an Ubuntu desktop it would be awesome if I could keep my mindmaps in dropbox and open them on my tablet using Simplemind.
Technically I can but in practical application it's one or the other. Work on the desktop with Freeplane or work on the tablet with Simplemind because Simplemind does not sync, it imports and exports. There's a huge difference. Sync is transparent and hassle free.
Back to searching.