What is the difference between cached maps and downloaded maps?

Downloading maps and map caching are two similar but distinct features. Both improve map performance and enable offline map viewing. Map caching automatically saves tiles viewed on the Maps page as you scroll and zoom. The cache limit is 250 MB; beyond this limit the oldest cached tiles are overwritten as new tiles are cached. Downloaded maps are downloaded using the Download Maps tool from within MotionX-GPS, where you define a specific region and range of zoom levels for downloading and storage. Downloaded map tile sets are stored on your device until you delete them.