BackgroundCachingCode(travelonline)

    [[RMConfiguration configuration] setAccessToken:kMapAccessToken];
    RMMapboxSource *tileSource = [[RMMapboxSource alloc] initWithMapID:kMapID];
    [tileSource setCacheable:YES];
    RMTileCache* cache = [[RMTileCache alloc] initWithExpiryPeriod:0];

    [cache beginBackgroundCacheForTileSource:tileSource southWest:CLLocationCoordinate2DMake(52.533827, 13.437938) northEast:CLLocationCoordinate2DMake(52.533828, 13.437939) minZoom:tileSource.minZoom maxZoom:tileSource.maxZoom];