Really Simple Moving Map Users Guide

Update: mobile version now released, in essence, a wrapper around the HTML5 web-app described here. Available in the iOS App Store, Google Play Store, or Amazon App Store.

What is Really Simple Moving Map ?

Really Simple Moving Map (or RSMM for short or #reallysimplemovingmap or #rsmm ) is one or more of the following (see the Limitations section later for a description of what it is not):

  • Browser-based (HTML5), platform-independent, device-independent, browser-independent mapping application with information, functionality, and features based on user-location derived from the devices' location services 
  • A substitute for the mapping / geo-location apps that come bundled with most devices (e.g., Google Maps, iOS maps etc) but which "never quite seem to do what you want"
  • Inspired by aviation, but not designed specifically for aviation. In fact, more suitable for use in urban or semi-urban settings where there is a good internet connection (see Limitations section)
  • Summary feature set:
    • "Moving map"  (with base maps provided courtesy of the excellent open-source OpenStreetMaps) which tracks your (device's) location, direction & speed of movement (based on successive location fixes), and altitude (based on GPS)
    • Point-ahead "time-line" indicating where you will be if you continued in a straight line (as-the-crow-flies) at your current speed 
    • [UPDATE July 2016: This functionality has been suspended due to the need to support SSL on Google Chrome, pending support for SSL by OpenWeatherMap] Add weather overlays on the map (courtesy of the excellent open-source OpenWeatherMap) including:
      • Temperature
      • Pressure
      • Cloud cover
      • Rain
      • City weather reports
      • Weather station reports
    • Day/night terminator overlay
    • Search for any location (globally) via Google search (and/or search the FlyLogical Cloud database), and pin a Marker on the map at the location resulting from that search
    • .... and/or click anywhere on the map and pin a Marker there
    • For any Marker you've pinned on the map (either directly or via search result):
      • View the bearing (to/from) and the distance between the marker position and your current location, plus the time it would take to reach the Marker location from your current location if you now headed directly towards the Marker at your current speed
      • View the sunrise & sunset times, and the remaining daylight hours (at the current time) for the given Marker location 
      • View the details of the Sun's track across the sky during the whole day (via the Sundial link)
      • Receive aviation weather briefings (decoded METARs & TAFs) from reporting stations nearest to the Marker location (determined automatically). Note: these briefings are an excellent source of global, real-time, weather information which are relevant to many activities beyond just aviation
      • Save the Marker location to the FlyLogical Cloud (database) for convenient re-use later (retrievable via the search functionality described above) 
    • Routes functionality whereby you can display a route (i.e., a series of connected waypoints) on the map, and monitor your current location and progress relative to that route. Again, aviation-inspired, the routes assume straight-lines (actually great-circles) between the waypoints, rather than, for example, road networks. This is in the interests of simplicity, and means that all navigation is "as-the-crow-flies" ("ATCF"). This approach is effective even for road routes (but you have to define the route segments to follow the road, RSMM does not do this for you). Route-specific portability features enable you to:
      • Create / import routes from a variety of sources
      • Export / save / view routes in a variety of ways / formats
    • A "breadcrumb trail" feature which records and displays your location history (i.e., a trace of where you've been)
    • As of 17 July 2016 (click here for example usage), Shapes functionality summarised as follows:
      • Create shapes and display them on the map. Available shapes include:
        • point
        • line (arbitrary number of vertices)
        • circle and circular arc (portion of circle)
        • square
        • rectangle
        • triangle
        • polygon (arbitrary number of vertices)
      • The shapes can be specified as being constructed from either Great-Circle segments (on a reference Ellipsoid), or from Rhumb-line segments (i.e., straight lines on Mercator projections)
      • For convenience, the shape coordinates are initialised via Marker locations, and then can be fine-tuned via edit-boxes
      • All visual attributes of the shapes can be customised e.g., line color & opacity, line thickness, fill colour & opacity, etc.
      • Save the shapes (individually or in groups) to the FlyLogical Cloud (database) for convenient re-use later (and for sharing with the public if desired)
      • Export the shapes (individually or in groups)  to KML file format (sent by email) for ease-of-use with KML-supporting apps such as GoogleEarth.

  • Integration with FlyLogical iNavCalc for aviation-oriented use (mostly for pre-flight-planning rather than in-flight navigation, see the Limitations section)
  • Free, no ads, though email registration required for some functions (mostly those that require email communication)
  • In some sense, an exploration into how far one can reasonably go with developing an HTML5-based, platform-independent,  mapping and navigation app which is "light" on the client-side / device, but which makes extensive use of Cloud Computing (shared server infrastructure) in the background (for the "heavy lifting"), and which can be easily extended to display additional "map layers" (such as the weather)

  • Getting started with RSMM

    RSMM  is easy  to use. Simply load the RSMM URL on your browser. As long as your device Location Services are appropriately configured (see the Gotchas section below), and as long as you have an internet connection (see the Limitations section below), within a few seconds of loading, RSMM will automatically display a map centred on your current location. If you are moving, the map will auto-refresh in order to keep track of your current position.

    The Display Panel located above the map displays a digital readout of your current position in a  user-selectable coordinate format (via the Options button / menu). If you are moving reasonably quickly -- walking pace or faster -- and if your Location Services have a reasonably decent signal e.g., via GPS rather than just WiFi, then the panel will also display an estimate of your current speed and heading (direction). Likewise, if the Location Services are providing a signal which is sufficiently accurate in three dimensions (GPS is generally required for this), the panel will also display an estimate of your "GPS altitude" (i.e., defined as height above the "reference geoid" -- not taking account of local topographical features). The units for speed and altitude display are user-selectable (via the Options button .menu). 

    RSMM is "always on". As long as the Location Services are providing a signal of sufficient accuracy, the display will continuously update with your current position, and the map will continuously refresh in order to track your position.  There is no "off button" (or "stop navigating" button as such). However, should you wish to temporarily "pan away" to look at other areas of the map, you can switch off the auto-panning feature of the map by toggling the "auto-pan" button (turning it orange).

    When you want the map to follow you again, simply hit the auto-pan" button again (turning it blue). The map will immediately pan back to your current location. During such times when "auto panning" is switched off, the Location Services remain active, so the digital readout of position etc will continuously update (it's just the map auto-motion that is temporarily disabled).

    Map Layers

    In addition to displaying your current position, you can add additional features to the map, via the Map Layers menu available via the Options... button. For example, selecting the Weather layers allows you to superimpose weather information on the map. The screen shot below shows an example with Clouds, Pressure (isobars), and Rain selected [displaying a depressingly familiar low-pressure weather system centred over the UK (!)]
    [UPDATE July 2016: This functionality has been suspended due to the need to support SSL on Google Chrome, pending support for SSL by OpenWeatherMap]

    Map Location Cursor Display Options

    The cursor which displays your current position on the map can be augmented as follows (via the Options...Navigation menu):

    Heading indicator (short blue stub attached to cursor) which displays your approximate direction of travel (as derived from successive position signals), expressed in degrees relative to True North

    Timeline indicator (thin blue pointer/line protruding from cursor), the tip of which indicates your approximate expected position at a given future point in time (set via Options...), assuming you maintain your current speed and direction of travel.

    Location error indicator (opaque circle centred on cursor), the radius of which indicates the estimated error in your position signal.

    The Search Controls

    The RSMM Search Controls allow you to find the location of pretty-much anthything, anywhere in the world. Type the desired name-to-search in the search panel, then hit Enter (or tap the Search button). RSMM will attempt a search of the FlyLogical database. This database primarily contains data-points of interest to pilots (since RSMM is inspired by aviation!), but it is also a repository of any waypoints which you have happened to save there (more on that later). In other words, you can use the FlyLogical database to create a library of your own waypoints for convenient re-use.

    If the search of the FlyLogical database proves successful, you are given the option to pin a Marker on the map at the location of the successful search. Alternatively you can choose to ignore that search result, which will automatically trigger a more general Google search. Likewise, if the initial search of the FlyLogical database proves unsuccessful, a Google search is then automatically performed.

    If the Google search  proves successful, you are given the option to pin a Marker on the map at the location of the successful search.


    Markers represent points-of-interest you've added to the map, either as the result of searching (see Using the Search Controls), or by simply clicking (or tapping) anywhere on the map. By clicking on the Marker itself, a popup Marker Info window opens. Here's a screenshot showing a Marker and its popup Marker Info window

    Marker Info Window: basic information

    The Marker Info window contains the following:
    • Save button. This lets you save the position of the Marker as a User Waypoint in the FlyLogical database. Once saved, you can re-use the Marker by searching for it via the Search Controls (just specify the name you gave when you saved it). Your saved waypoint is also available to the entire suite of iNavCalc  apps since they access the same FlyLogical database as RSMM. [Note: to edit an already-saved waypoint, or to delete it from the FlyLogical database, you need to use the iNavCalc Waypoints Manager within the iNavCalc web app since RSMM currently only facilitates the creation of new waypoints in the database, and not editing thereafter].
    • Remove ? button. This lets you remove the Marker from the map. Note: this simply clears the Marker from the map display, it does not delete it from the FlyLogical database (if you have saved it there). [Note: if you wish to remove all Markers from the map at once, click the Remove User Markers ? button (located top-right of map view surface), rather having to remove them individually].
    • Name of Marker (or "User Marker" if un-named)
    • Location of Marker, coordinate format can be selected via the Options button
    • Sunrise and sunset times for today's date
    • Daylight hours remaining (from current time)
    • View the details of the Sun's track across the sky during the whole day (via the Sundial link, see below)
    • Radial (direction measured relative to both True and Magnetic North), and distance (in units which can be selected via the Options button) from the Marker to your current location. The direction corresponds to the direction someone would have to steer if they were at the Marker location and wanted to head directly towards your current location. For long distances (such that Earth curvature makes a difference), the direction corresponds to the starting direction of the great-circle arc between the two locations.
    • Bearing  is the reciprocal of the Radial direction. In other words, this is the direction (or starting direction of the great-circle arc) you would have to steer if you wished to head directly towards the marker from your current position.
    • Time it would take for you to reach the Marker location from your current location if you headed directly towards the marker (i.e., if you immediately set course along the Bearing) and maintained your current speed.


    Clicking on the Sundial link in the Marker Info window opens the Sundial window:

    ...which shows the  track of the Sun across the sky today for the selected location. The highlighted value corresponds to the position of the Sun right now (i.e., at the point in time when the Sundial link was initially clicked, then refreshed every minute thereafter). Clicking anywhere on the trajectory shows the Sun position at that point on the trajectory (in terms of time, direction --true and magnetic, & height above horizon), in increments of 5 minutes.

    Marker Info Window: additional options for registered users

    If you have registered with FlyLogical and have logged-in to RSMM (via the login button located top-right of screen), additional information is available in the Marker Info window, as follows:

    • Aviation weather briefings (METARs and TAFs).  RSMM will automatically identify which aviation weather reporting stations are located nearest to the Marker location, and retrieve the METAR ("actual" weather briefing)  and TAF ("forecasts") for each station. You can specify (via the Options button on the main map view surface) the number of stations to report (1, 5, or 10 nearest); whether you wish to include "de-coded" as well as the raw reports in the display, and the units used to present the various quantities in the de-coded reports. The two screenshots following present example displays with and without the de-coded option enabled, respectively. The de-coded reports in particular are relevant to many pursuits beyond aviation, by providing global up-to-date detailed weather "current" and "forecast" conditions. 
    • Density-Altitude. The is the effective altitude defined according to a standardised model (the "International Standard Atmosphere") at which the atmospheric density in that standardised model equals the actual atmospheric density at the location & elevation of the given weather station.  This is most likely to be of interest primarily to pilots, since it gives an indication of the expected performance of the aircraft engine. A low Density-Altitude corresponds to high atmospheric density (which, in turn, corresponds to the combination of high atmospheric pressure and low atmospheric temperature). Engines perform better under conditions of high atmospheric density (i.e., low Density Altitude), whereby they get plenty of oxygen to burn the fuel. By contrast, under conditions of low atmospheric density (i.e., high Density Altitude), engines perform poorly, and the aircraft may not even be able to get of the ground for a given length of available runway. [For fun, use RSMM to check the Density Altiude of Denver, Colorado...on hot days, the Density Altitude can be so high that the engine performance of light aircraft can be so poor that the aircraft will not be able to reach take-off speed before reaching thye end of the runway. Always good to check.]

    • The Email... button (located at the start of the weather briefing display) allows you to receive the METAR and TAF reports via email. Simply tap the button, and you will be prompted to confirm that you indeed wish to receive the MET via email. If so, within a few moments, you will receive the MET report (raw METAR and TAFs) via  (PDF) email attachment. The email address which you specified when you registered with FlyLogical will be the one that receives the email.
    • The Twitter... button (located beside the Email... button) allows you to receive the METAR and TAF reports via Twitter. Simply tap the button, and you will be prompted to confirm that you wish to exit the RSMM app in order to be transfered to Twitter where a Tweet will have been "prepped" for you to send.  All you need to do is send that Tweet (or not, if you choose to abandon at that point). The Tweet has been specially formatted to be parsed by FlyLogical's Twitter parser. It is important that you send the Tweet "as as" and do not alter it in such a manner that you inadvertently affect the automated parser's ability to decode the Tweet). Within a few moments of sending the prepped Tweet, you will receive a reply Tweet (from @Flylogical) which contains an embedded link to the MET report. You can then ReTweet this reply should you wish to distribute the MET report to your followers. The embedded report will expire after a day. [Note: the functionality of this Twitter... button is basically a wrapper around the FlyLogical "Twitter App"]
    • The Refresh... link  (located above the Email... button) allows you to update the MET briefing by triggering a request to retrieve the latest MET data without having to exit-then-re-open the Marker Info window.

    Markers list

    Clicking the Markers button (located top-right on map, note: this used to be labelled Remove User Markers ?) opens a window containing a list of all your User Markers, as illustrated in the screenshot below. 

    Clicking on any entry gives you the option to pan the map to the given Marker location. The default list ordering has the most recently-created Marker at the top. Clicking on the User Marker heading enables you order the list alphabetically.

    The Clear all User Markers button (located above the list) enables you to clear all Markers from the map. Note: this does not delete them from the FlyLogical database if they happen to be saved there.

    Working with Routes

    RSMM allows you to display a route (i.e., a series of connected waypoints) on the map, and monitor your current location and progress relative to that route. Aviation-inspired, the routes assume straight-lines (actually great-circles) between the waypoints. The screenshot below shows an example of a route displayed on the map.

    Clicking any segment ("leg") on the route, makes that the "selected leg". It becomes highlighted (in magenta). The shortest distance between the selected segment and your current position is displayed in the main Display Panel as your "Off-track" distance (displayed to the right of your location coordinates). The screenshot below illustrates this. The first leg (of the above route) has been selected, and your off-track distance (of 2 nautical miles, units selectable via Options...) is displayed.

    Creating / Importing Routes 

    You can create or import a route into RSMM in a number of different ways via the Route... button (requires login), as follows:

    Remove the route from the map. Note: this does not delete the route from the FlyLogical database (if it happens to be stored there), it only clears it from the map display.
    Create a route from the collection of Markers currently pinned on the map. During the creation, you are given the option to connect the last point to the first (if you wish to create a closed loop round-trip)
    Create a route from a specified list of named waypoints using iNavCalc's command-line functionality e.g., "KSFO KLAX" (see here for a quick introduction on how to create routes via the iNavCalc command-line)
    Import a route from RouteView by copying-and-pasting the URL from the RouteView browser address bar.
    Import a route from a ".gpx", ".fpl" (Garmin), or ".flightplan" (SkyDemon) file. This works well on desktop machines, ultrabooks, and Android devices, all of which support general filesystem access (unlike iOS, which does not)
    Import a route from by copying-and-pasting from the PlainText Link export feature
    Import a route from the FyLogical database which contains a collection of publicly-shared routes, as well as being a repository for your own routes library

    Exporting / Saving Routes

    You can export or save a route from RSMM in a number of different ways via the Route... button (requires login), as follows:

    This lets you save the route in the FlyLogical database. Once saved, you can re-load it via the import from FlyLogical cloud... function described above. . Your saved route is also available to the entire suite of iNavCalc  apps since they access the same FlyLogical database as RSMM. [Note: to edit an already-saved route, or to delete it from the FlyLogical database, you need to use the  iNavCalc web app or iNavCalc mobile apps since RSMM currently only facilitates the creation of new waypoints in the database, and not editing thereafter]. 
    Export the route to ".gpx" and ".fpl" (Garmin) file formats via email attachment. The email address which you specified when you registered with FlyLogical will be the one that receives the email with the attached route files. Of interest to pilots, the email export interface uses the full iNavCalc command-line should you wish to specify additional parameters to control the PLOG which accompanies the route files. The complete range of available command parameters is described here. Non-pilots can ignore this feature, leave the box blank (and ignore the returned PLOG etc).
    On clicking this button, you will be prompted to confirm that you wish to exit the RSMM app in order to be transfered to Twitter where a Tweet will have been "prepped" for you containing an embedded link to the RouteView  representation of the route (see next option) which you can share with your followers.
    On clicking this button, you will be prompted to confirm that you wish to exit the RSMM app in order to be transfered to the RouteView  web-app with your route pre-loaded.
    On clicking this button, you will be prompted to confirm that you wish to exit the RSMM app in order to be transfered to the web-app with your route pre-loaded.

    Using the Trail Feature 

    RSMM has a simple "breadcrumb trail" feature whereby you can record and display the history of your position (albiet with some caveats, see the Limitations section below). To active the feature, use the Trail... button located on the main map view surface. Within the corresponding popup window, you can toggle the activation status of the trail recording, show/hide the trail on the map, and delete the trail history.

    The screenshot below shows an example of the breadcrumb trail displayed on the map (the pink trace behind the location cursor).


    Make sure that the browser you are using to load the RSMM app has been granted full rights to access the Location Services on your device. This is relatively straightforward to configure on most platforms, though may require a certain amount of clicking through the various system options / security & privacy settings / configuration / menus.  Once you have granted these Location Services rights to the given browser,  the first time you load the RSMM URL in the browser, you will also be prompted by the browser to grant the same Location Services access rights to the specific RSMM web site.  If you choose not to grant these rights, RSMM will not be able to make use of the Location Services on the device.

    Known Issues

    RSMM has not been exhaustively tested  in a formal sense, but the following issues have been noted:

    • On Internet Explorer 11 running on a Windows 8.1 Acer Aspire S7 ultrabook, the app seems to run fine except that IE hangs on occasion 
    • On Windows Phone 8 (a Nokia device) the app seems to function,  except that the (IE) browser seems to hang reasonably often 

    The point to note is that RSMM wholly relies on the HTML5 standard. Not all platforms are compliant with the standard to the same degree. This may -- or may not -- be the explanation for the issues noted. Of course there may be bugs in the RSMM software, but the serious ones would have become apparent on the other platforms (notably Android and iOS) which seem to work well.

    Please feel free to provide any further observations you may come across regarding the stability of the app via the Comments feature of this blog (bottom of this page)


    • Being a web app, an active internet connection is required for all RSMM functionality to work smoothly and correctly. That's why it is most suited for use in an urban or semi-urban setting i.e., where there is generally a 3G/4G/WiFi signal available. That said, the core location services should work "offline" even without an internet connection as long as the device has a GPS sensor (internal or peripheral) suitably configured to feed the (HTML5) location services layer, and as long as the app has been previously started (i.e., the app web site URL visited) when an internet connection was available. Under those circumstances, as long as the GPS signal is available, the app's position, speed, and heading displays will continue to update in "offline mode" even without an internet connection. The map however will not update without an internet connection. As such, if new tiles are required whilst the internet connection is down, grey blocks will appear (instead of new map tiles) until such times as an internet connection becomes available again. However, the position cursor and breadcrumb trail will continue to update in "offline" mode (as long as the GPS signal is valid), albeit against a background with grey blocks. If you wish to use the app when you know that there may be an internet dropout, make sure you have the map zoomed-out to cover the entire area of interest before the internet connection drops. That way, the map cached in the device should be sufficient without needing the tiles to be updated.
    • Being fundamentally a browser-based app (relying on HTML5 technology), RSMM's breadcrumb Trail feature will only record smoothly and continuously when the app web-page has primary focus on the device. In other words, if the web-age loses focus (e.g., if you temporarily move off to another web-page or another app,or if the device enters hibernation/power-saving mode etc), then the Trail recording will be correspondingly interrupted. It will recover when the app web-page regains focus, but there will be "jumps" in the recorded Trail, corresponding to the periods of loss-of-focus. [Hint: to work around this on a mobile device, you can launch the browser via a third-party app which enables the screen to remain permanently open. For example, Car Home Ultra on Android works very well]. 
    • In a trade-off between feature-richness versus efficiency for mobile-rendering, the choice was made to use the open-source leaflet.js map rendering library for RSMM. One of the limitations of this library is that the map is always rendered "North Up". It is not possible to switch to "Track Up" etc. As a workaround, disable the auto-rotation of your device's display, and physically rotate the device in your hand for "Track Up" (like you would a physical map!). This works well for phones and phablets, though not so well for larger tablets or ultrabooks.
    • For simplicity, all navigation in RSMM is "as-the-crow-flies" (ATCF), inspired by aviation rather than driving 
    • Fundamentally, to get around the above limitations, use a real GPS device (rather than RSMM) for real navigation. Horses for courses, as they say.