OsmAnd: offline mapping for mobile devices

OsmAnd is an open-source application that gives access to offline maps, based on OpenStreetMap on your mobile device. Features include trip recording, reading/writing .gpx files, route planning and navigation. It is available for free in the Google Play and Apple App stores.

I have come to find it invaluable for travel and fieldwork in places with limited access to mobile internet. This post provides an introduction.

Background

Free/libre and open source software (FLOSS)

You can install and run OsmAnd on your phone without paying. In this sense it is free (“gratis”) or “free as in beer”. However, and very importantly, it is also open source software which is free (“libre”) or “free as in speech”.

Free/libre open source software is special because users are given access to the “source code” that is used to create the application. This allows those with the skills to see how it works and to modify it to fit their purposes. An analogy for this would be the cars of the 1990s, which users could take to any garage for servicing and upgrades, compared to those of today that can only be worked on by vendor-approved garages with special tools. QGIS is an example of open source geographic information systems software. In this case, many people have contributed improvements and the software has evolved rapidly.

Much free (“gratis”) software comes at a price. It may bombard you with on-screen adverts or side-load unwanted packages such as browser add-ons. Alternatively, the app may spy on you and sell information, such as your precise location, to data brokers and advertisers. Instagram and TikTok are examples of the latter. This is less of an issue with FLOSS software because someone could just make a version without the adverts or tracking.

When installing a new application on your phone, you can get a sense of how much it is likely to track you by looking it up at exodus-privacy.eu.org.

Crowd-sourced maps with OpenStreetMap

Open Street Map is a crowd-sourced mapping project. You can think of it like Wikipedia for maps, because anyone can edit the data. Over time, the data have become extremely rich, particularly because freely-licenced data from national mapping agencies e.g. XXX from the Ordnance Survey in the UK, have been incorporated into the system.

One advantage of Open Street Map data over something like Google Maps is that data can be updated very quickly and new buildings or roads often appear there first. Another is that very detailed local knowledge can be captured e.g. paths through woods used by runners or dog walkers. A disadvantage is that coverage can be patchy and if no-one has taken interest in a region to map the features then the map will be sparse.

OsmAnd uses Open Street Map data to provide the maps. The data are in “vector” format, which allows OsmAnd to change the mapping style on-the-fly, to search for addresses and points of interest and to perform routing calculations to give driving directions.

Installation

There are good online instructions for setting up OsmAnd here.

It is useful to have access to a good internet connection when you first install OsmAnd. First, install it from the app store on your device. You will need to give it permission to access your precise location, at least while using the app.

The initial installation doesn’t include any map data. When you first open it, it will find your location and offer to download map data for your location. This may be hundreds of Mb, depending on how rich the mapping is in the area. It is also worth downloading the world overview.

Useful Features

Trip recording

I use the trip recording function to record a track of where I have been. This is similar to functionality provided by fitness trackers such as Strava.

Read/write .gpx files

OsmAnd can read and write .gpx format files used for sharing GPS data, including tracks and waypoints. As such it can act as a drop-in replacement for a hand-held GPS, while my smartphone camera has already saved me from carrying a dedicated digital camera.

Route planning

The route planning tool will use tracks and roads to link points of interest. It will use different settings depending on whether your mode of transport is foot, bike or vehicle. The algorithm can be configure to optimise for shortest distance, quietest routes or least elevation gain. It is great for finding adventurous off-road cycle outings or trail runs.

The route can be exported as a .gpx file that you can use with Strava or similar.

Navigation

OsmAnd can also do route navigation and give turn-by-turn directions. Because all the map data is stored locally, it doesn’t use any mobile data and works even where signal is low. I’ve found the algorithm to do a good job.

A slight disadvantage compared to an online system such as Google Maps is that it doesn’t have access to live traffic information, so it cannot take that into account when planning a route.

OsmAnd+ and OsmAnd Pro

The OsmAnd application is a fully-functional mapping tool that provides all the features above. There are also a paid versions available, OsmAnd+ and OsmAnd Pro, these are also in the Google Play and Apple App stores.

OsmAnd+ includes additional features:

• Unlimited basemaps with monthly downloads. This is most useful if you are travelling between many densely-mapped areas.
• Contour lines, hillshade and slope information (based on Shuttle Radar Topography Mission data)
• Android Auto compatibility

It is not very expensive (XXX), and I think it is well worth it.

In particular, the contour line and hillshade features are valuable when navigating in areas where there are few mapped features between / along roads. The display of topographic information allows you to recognise nearby hills or the gradient of the route that you are on, which helps you relate your position on the map to your surroundings.

The example below shows an example area north of Harare, Zimbabwe, with and without the topographic information visible.

picture here.

OsmAnd Pro has all the features of OsmAnd+, plus others:

• Cloud storage for synchronising data between devices
• Hourly base map updates
• 3D relief maps
• Weather information
• Integration with car diagnostics systems e.g. to track fuel consumption

It has a EURO2.99 per month subscription.