@Nullable
    private static Boolean getActiveMapFilterSavedDifferently(final GeocacheFilterContext filterContext) {
        final GeocacheFilter filter = filterContext.get();
        if (filter.isFiltering()) {
            return filter.isSavedDifferently();
        }
        return null;
    }
Applies given filter to cache list. Additionally, creates a second list additionally filtered by own/found/disabled caches if required
main/src/main/java/cgeo/geocaching/maps/MapUtils.java