: The free version of the CalTopo App is available for iOS and Android. Note that while the app is free to download, a paid subscription is typically required for offline map storage.
: This site is an excellent source for high-resolution topographic data, including LiDAR, provided by OpenTopography . Topo Map Free
: For those in New Zealand, topos.nz offers free online and offline mobile access to LINZ topographic data. Quick Guide to Reading Topo Maps : The free version of the CalTopo App