First at all thanks for this really great map app!
I think you are at the momant working on several map format supports (for example rmaps). My wish is now, is it possible to support the OSM PDF vector map format (http://http://wiki.openstreetmap.org/wiki/PBF_Format
)? I found some informations on the web an there is also a Java and C PBF libary available (http://https://github.com/scrosby/OSM-binary
) so it should be possible to add the format to Locus.
The code ist under GNU LGPL is this a problem?
A big advantag beside the vector format is that a lot of maps are available in the web...
So maybe you can think about it to support that format!