> Blogs > Archived Blogs > Mapping tools for botanists, part two: Locus Map

Mapping tools for botanists, part two: Locus Map

The second in a series of reviews of mapping tools by Kew's Geographic Information Science (GIS) Unit: this time we look at an app for mobile mapping called Locus Map.
Blog team: 
Steve Bachman

The end of paper maps?

Paper maps have always been an essential component of botanical fieldwork. Prior to the trip they can be used for planning purposes like helping to define target areas for fieldwork, identify potential obstacles, plan road trips and, of course, whilst in the field they provide an essential navigation tool.

However the days of the paper map may be numbered as digital mapping goes mobile. Over the last year the GIS team have been testing out new mapping software on smart phones and seeing how effective they are in the field. One of the most promising products we’ve seen is called Locus Map and it is available for devices using the Android operating system. We put Locus Map to the test during several recent field trips and here is the verdict:

So what is Locus Map?

Locus Map is an application or ‘app’ that can be used on smart phones. Specifically, it can be used on the Android operating system, so is not available on Microsoft or Apple. On the simplest level, Locus Map puts a map on your phone and, of course, the great thing about smart phones these days is that they usually have an integrated Global Positioning System (GPS) receiver. So, if your GPS is on and you start up the app you will see exactly where you are and where you are going.

The extensive array of options are too numerous to review entirely so we’ll give a brief overview of some of the main features that we found useful:

Waypoints and tracks

Anyone familiar with using a GPS device will be at home with the waypoints and tracks options on Locus. You can record, pause and stop a tracklog and numerous settings allow you to control the way the track is recorded e.g. minimum distance between points and various style options. You can even allow Google’s MyTracks to take over recording.

The basic ‘Add point’ feature is the same as a standard waypoint. You have numerous options to customise how this is displayed on the map e.g. symbols and colours and you can group these into different categories or layers e.g. new observations for trees or good places to camp! When adding the point you can set the location in numerous ways e.g. GPS co-ordinates (most likely), but you may wish to add a waypoint some distance away from your exact location e.g. a vegetation patch in the distance, and this can be done by selecting the location using the cross-hairs on the map. There are notes fields to add additional pieces of information and even the ability to add you own custom fields, something most standalone GPS devices do not have. With the smartphone you also have the advantage of being able to enter text rapidly using the many text options including predictive text tools such as SwiftKey. Finally, it is worth pointing out that there is an ‘Add Photo point’ feature which is exactly the same as the add point feature described above, but with a photo.


As you would expect, all the standard navigational tools are built in. The compass can be used to guide you to a point of interest or a waypoint. A neat feature I found myself using a lot is ‘Guide to’ which allows you to choose a point on the map and it will show you direction and distance from that point. There is also a ‘Show view’ option which indicates the direction of view - simple, but very handy.

Offline maps

Having a good GPS is one thing, but looking at a dot in the middle of a white screen doesn’t help you a great deal. We need to have context in the form of base maps to help us understand where we are. Many smartphone mapping tools provide these base maps e.g. Google Maps, but they are downloaded to the phone so they incur data charges as you roam. When taking your phone abroad you are likely to incur significant data charges as your phone downloads more map tiles when you move around. The way to overcome this problem is to download an entire map before your trip so that it can be viewed even if you are offline.

There are two main types of map you might want to download: a vector map with points, lines and polygons (e.g. cities, road/rivers and lakes/vegetation patches etc.) or raster maps, which are usually satellite images. These help to provide context and highlight interesting features that you may want to visit. Locus provides some nice links to standard vector and raster basemaps that can be easily downloaded and made visible in your map viewer. Switching layers is very easy using the Maps icon.

Offline maps is also a way to get your own data visible on the phone. On a recent trip to Ethiopia for example, Jenny from the GIS team prepared a model of Coffea arabica distribution and imported this into Locus so that in the field, when she found coffea populations, she could see what the value of the model was at that site. Note that in some cases you may need to transform your data in order to get it into the right format. We use a package called MAPC2MAPC to help with that process.

Format support

Locus is extremely versatile in terms of file format options thereby making the movement of data on and off your device extremely easy. Prior to our trip to Madagascar in June this year I converted data from our BRAHMS database to KML format and then loaded that directly into Locus, thereby giving us all the locations of specimens that we wanted to visit. (see map below)

Pro version

As with most apps nowadays there is a free and pro version. So what do you get with the paid pro version? Well one thing you won’t get if you go pro is advertisements, but aside from that it is mostly the removal of limitations in some of the features.


  • Smart and clean user interface and very easy to use
  • Great feature list
  • Good developer support - constant updates and improvements
  • Customisable right sidebar - add only the features you regularly use to help keep your interface clean
  • Links to other mapping systems e.g. save your tracks directly to Google ‘My Tracks’


  • The wide array of options means it is occasionally hard to find certain features
  • Pro paid version is needed to ensure there are no limitations on all features
  • Some ‘add-on’ apps needed to enable certain features e.g. Bluetooth support

Final summary

In our opinion Locus Map is proving to be far and away the most useful mobile mapping app we have discovered to date. The app is stable and user friendly and has proven to be a real asset for fieldwork. If you have found something better let us know!

- Steve -

Related links