USGS Home Logo and link to The National Map
Using TNM Data on Mobile Devices

USGS The National Map Data on Mobile Devices

Android and iPhone users can now use their mobile devices as digital topo maps, leveraging USGS maps together with the power of GPS to map their location while hiking, biking, running, or any other activity that benefits from precision navigation. The type of data that are available includes USGS imagery and topographic maps from The National Map (TNM), as well as road and contour layers. The following apps include USGS services in the list of available online maps:

To use TNM data on your Android device:

  1. Install either OruxMaps, AlpineQuest, or Gaia GPS via Google Play App Store.
  2. Access TNM data through these three applications as a dynamic, online layer.
  3. Switch map sources to view either TNM Topo or Satellite data through the application.

To use TNM data on your iOS device:

  1. Install either Gaia GPS or Galileo Offline Maps via iTunes Store.
  2. Follow instructions to add TNM data on Galileo at
  3. Switch map sources to view either TNM Topo or Imagery data through the application.


Additionally, TNM services support MOBAC, the Mobile Atlas Creator. For users that may be navigating in an area that is outside of cell phone coverage, MOBAC ( allows users of this desktop application to build small "mobile atlases" with USGS data. These "mobile atlases" can be built over any area of interest at multiple scales, and when completed, the small file is moved to the phone. "Mobile atlases" enable GPS applications on both iPhone and Android mobile devices. By storing this small amount of data on the phone, these "mobile atlases" ensure the topographic data is available even when cell coverage is not.

Follow these instructions to build map files that will allow an Android or iPhone to use USGS TNM data when network connectivity is not available:

  1. Download the MOBAC desktop application (
  2. Unzip the downloaded file and activate the "Mobile Atlas Creator.exe" file.
  3. Indicate the mobile application in use (Galileo, AlpineQuest, etc.) and highlight an area of interest to build an offline map file.
  4. Select the appropriate scales.
  5. Select "Create Atlas". Move the resulting folder and map data to the appropriate folder on the mobile phone.
  6. More information on using MOBAC is available through the "Quick Start Manual" (

Disclaimer: Any use of trade, firm or product names does not imply endorsement by the U.S. Government. No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the accuracy and functioning of the commercial software programs cited in this Technical Announcement, and the U.S. Government shall not be held liable for improper or incorrect use of The National Map topographic data from USGS.