Overview of saving map and exiting ArcPad
After you finish working on a map, you can save it and exit ArcPad. You save it as an ArcPad map file and store it on your computer or your mobile device. ArcPad automatically appends a file extension (.apm) to your map document name when saved.
Compact Flash and Secure Digital Memory Cards: Consider storing your data on Compact Flash (CF) or Secure Digital (SD) Memory Cards. This will ensure that your data is not lost if the battery on your mobile device is drained.
See section 'Memory and Storage Capacity' under Selecting a Mobile Device for more information on storage cards.