Android Maps and Aerial Photography

Android mobile devices need an Android map to be able to navigate with the help of GPS. Maps are downloaded and stored in a GPS device. These maps can be viewed online or offline depending on your choice of a GPS app. Backcountry Navigator Android GPS app is capable of these.


Topographic Maps
Topographic mapping is created by US Geological Survey in the United States. Every inch of the US is covered by 54,000 map sheets or quadrangles. The primary scale they use for topo mapping is 1:24,000 which means that one inch on the map equals 24,000 inches on the ground or 2,000 feet. These map sheets demonstrates an area of that is 7.5 minutes of longitude wide by 7.5 minutes of latitude high and measures just about 29 inches high and 22 inches wide.


A topographic map shows the shapes and terrain of the land and uses signs to symbolize the topography of the area.

A handy alternative for a map sheet is an Android gps map. It function like map sheets in an Android GPS device. With the use of Backcountry Navigator GPS app, it can also be used for planning, preparation and navigation.

There are seven colors on a topo map representing the type of terrain features. An exception is the Northern areas of Canada, which are mapped in monochrome (or black and white).
•    Black defines features such as buildings, train lines, power transmission poles, toponymy, exact elevations, border and neighboring information.
•    Red represents concrete roads, highway numbers, crossing points and major transportation routes. A red hue signifies an ongoing urban development.
•    Orange means undeveloped roads, unidentified roads and streets.
•    Brown indicates outlines of elevations, eskers and contour lines.
•    Blue represents water features, names of bodies of water and watercourses. Universal Transverse Mercator matrix is also shown in blue.
•    Green colors in topo maps means wooded areas and plantations.
•    Grey is used for uncategorized signs, glossary of terms and abbreviations found at the back of the map.
•    Purple indicates updates added to the original map detail.
 
One of the most important information to look for on a topographic map is the latest date of revision printed on the left side of the scale. Even though mountains take hundreds of years to change, small-scale features change quickly. A watercourse may change because of flooding and landslides and alter the topography considerably. Some trails may have been added or some may have become unusable. These small changes are still very important to ensure accuracy and safety.

Aerial Photography
Since aviation began more than a century ago, aerial photographs served as the source of information about the Earth's surface. The success of cartography came from precise aerial photos.
An aerial photograph gives a specific view of the ground that no other map can. During emergencies when information cannot be accessed through maps, aerial photography is the best alternative. An aerial image gives a permanent and exact record of a monitored area on a daily basis.

Aerial photographs cannot be compared to a topographic map as both have different characteristics. Ground features in aerial photos are hard to interpret without symbols and the scales are only approximate. The lack of contrasting colors and hue makes it difficult to use in the dark. However, nothing can surpass the benefits of an aerial map in times of disasters where information is most important for safety and prevention.

Android maps, aerial photograph and Backcountry Navigator in your Android GPS device can give you information about your exact location and Earth’s geographical status anytime.