Android Download Map Tiles

I do not get fully what you want to get. Perhaps you should download tiles in parallel with map showing inside the application. Library does not have specific downloader for this.

You can also define permanent cache to the SD card, so next time map does not need to be downloaded.

Following code controls also that not too much
of space is taken for the cache:

     final MemoryCache memoryCache = new MemoryCache(1 * 1024 * 1024); // 1MB

            // final File cacheDir = this.getCacheDir(); // maybe it is not safe to use it
            final File cacheDir = new File("/sdcard/maps_lib_cache");
            if (!cacheDir.exists()) {
                cacheDir.mkdir();
            }
            if(cacheDir.exists()){
            StatFs statFs = new StatFs(cacheDir.getAbsolutePath());
            int freespace = statFs.getAvailableBlocks() * statFs.getBlockSize();

            Log.debug("Free space of " + cacheDir.getAbsolutePath() + " is "
                    + freespace);

            int cacheSizeWish = 10 * 1024 * 1024; // 10 MB

            // do not take more than 50% of free space for caches
            int cacheSize = (cacheSizeWish * 2) >= freespace ? (int) freespace / 2
                    : cacheSizeWish;

            Log.debug("File cache set to  " + cacheSize);

            final AndroidFileSystemCache fileSystemCache = new AndroidFileSystemCache(
                    this, "network_cache", cacheDir, cacheSize);
            
            mapComponent.setNetworkCache(new CachingChain(new Cache[] {
                    memoryCache, fileSystemCache }));
            }else{
                mapComponent.setNetworkCache(new CachingChain(new Cache[] {
                        memoryCache}));
            }