What is this?
This map shows the position of someone based on multiple tracking devices. It attempts to show data from all available sources, but highlights the most current. This avoids needing to check multiple different sites for the various technologies and instead shows everything in a single place. The information displayed here updates automatically, but is somewhat delayed from the acutal data sources. That means you do not need to refresh this page and any new data will update the markers on the map. If the compass is highlighted, then new data will cause the map to automatically pan to the newest available position. If the page is unable to fetch the latest data, then you will see a icon at the top. This occurs only if the system fails to show you the latest available data. If no data has been received from the trackers, you can see that in the "updated" time in the pop-up.
Why are there multiple icons on the map?
Each of the available data sources are shown on the map. The
latest one will appear "solid" 
while older sources will appear
faded or "semi-transparent" . If you click on a
marker, it will show you when it was last updated, as well as
other information about the source.
To automatically center the map on the most recent position, click on the compass icon on the top right, which will automatically move the map so the latest position is shown in the center. If you click on the tracker list icon on the top right, all the known trackers will be displayed (newest at the top). Click on one to jump to it on the map.
In addition to markers that indicate a tracking device,
messages (which look like 
) that are sent from one of those devices
will appear on the map in the location where they were
sent. Click on the message to view the message text itself, as
well as when and from what device it was sent). You can also
click the icon on the top right
to show a full list of all messages.
What are the colored lines?
Each marker may have a colored history line trailing it, which shows where the marker has been in the past. This gives you an idea of where the marker has been, and potentially where it may be going in the future, if you can imply a direction from it. If a line looks like a jumble of lines going all over the place over a single point, it means the marker was reporting its position mostly in the same place, but error in the GPS position caused it to drift around over time.
By default, only the history line from the most recently updated tracker will be shown, to avoid confusion over multiple lines. To see the history line for one specific tracker, open the tracker list and select a different one.
What types of trackers am I looking at?
If you click on a marker, the pop-up will give you information about the tracker, including the type. The available types are:
- inReach: A satellite tracking device that uses the Iridium Satellite Network to sent position reports to the Garmin servers. This happens at most every 10 minutes, but may be less frequent if the device does not detect that it has moved lately (to save battery). In general, this should work most places on the planet, but it does require a clear view of the sky, so it may not work in canyonous regions. These devices are handheld and may be attached to a vehicle or taken out and carried somewhere on foot.
- APRS: A tracking device that uses amateur-radio to broadcast its position to one of many ground-based repeaters and/or gateways, which ultimately ends up at aprs.fi. This usually happens more frequently when moving quickly (up to as often as once per minute while driving on a road) and less frequently when stopped. This works in places where there is volunteer-run infrastructure that is reachable, which may include very remote areas when a mountaintop repeater is available, or when the transmitter is high enough to have a clear view to a gateway. These devices can be built into a vehicle (which means they really only report where the vehicle is) or handheld (which could be in a vehicle or carried by someone on foot).
How do I know if the data is up-to-date?
All of the tracker technologies involved have limits, both in how frequently they transmit their position, but also in how that information makes it to the internet. The "Updated at" time in the pop-up indicates when that position report was sent, and the latest one of all shown (see the trackers list display) is the latest available information. If the latest information seems to be old, this may be because the device is out of range of a receiver, or is unable to transmit to the receiver (or satellite) because of terrain, tree cover, weather, etc. The tracker may also be turned off, out of batteries, or is transmitting much less often than normal because no movement is detected and it is attempting to save battery power.
How long is data available?
By default, only the last 24 hours of data is shown to keep it clean. However, if you open the tracker list , you can select to see a longer period of history.
How do I know if something is wrong?
If trackers are moving, there's a good chance that everything is fine. Further, in almost all cases, it is possible to get a message out indicating that there is a problem. Check the message list on the right side to see if any have been received. If available, any plans or scheduling information will be posted in the plans section, available on the right side.
What kinds of maps are available?
The layer control
provides the ability to switch the base map displayed, which may
provide more useful information depending on the area. The maps available may be:
- USGS Topo: A good general-purpose topo map with 3D shading (and regular topo lines) which works well for urban and rural areas.
- USGS Forest: A highly-detailed topo map, scanned from the maps the forest service tends to use for their own purposes. Useless when zoomed far out, but extremely detailed when zoomed in.
- USGS Satellite: Free-to-use satellite imagery provided by USGS, but without labels or other indicators.
- Thunderforest Outdoors: A good "outdoor recreation" map from the Thunderforest project. More attractive than the base USGS Topo map, but more restrictive in terms of use, and not nearly as detailed as the USGS Forest map.
- Open Street Map: The default tile set from the OSM project. Lots of detail, usually quite accurate and up-to-date, but not pretty and not particularly good for wilderness areas.
What other environmental information is available?
Some aspects of nearby weather can be shown:
- NEXRAD Weather Radar can be overlaid on the map by clicking the button on the toolbar on the right. This plays a loop of the last hour of radar imagery. Click the resulting loop time box to hide it again.
- MESONET Weather Stations near by a tracker can be queried for local conditions. Click the "Show nearby weather" link in the pop-up for a tracker to show it. This is limited to available data, as well as availability of the MESONET weather API service.
- OpenWeatherMap data may be available, including things like Rain, Wind, Temperature, Cloud cover, etc. Select one of those add-on overlays in the layers box.
How do I find information on this map to render help?
If the person being tracked here needs help and you are trying to give information to someone planning to render help, you need to collect information from this page to help them. First off, write down everything you see here, because as time goes by, old data will be removed from this page, which may be valuable depending on timing. The information needed for rendering aid will almost always be at a minimum:
- Where the person is (i.e. the latitude and longitude shown as "coordinates" in the pop-up when you click on one of the markers)
- When the person was known to be at the coordinates (i.e. the time shown as "updated at" in the pop-up).
- Which direction the person was moving, if they are moving. This may be as easy as reporting what is shown as "movement" in the pop-up, but this value can only be trusted if the person was moving consistently in that direction when the position was reported. Ideally, confirm the general direction based on the colored history line, which shows where they have been.
- You may also want to report other historical information, such as "their handheld tracker was also reporting them as away from the car an hour ago, so they may not be with their vehicle."
- If an inReach device is shown here, report the identifier as agencies may often be able to send messages to these devices directly (the string reported as "data from" in the pop-up).
- Note any messages that were sent from any device, where and when, in case they are relevant (click the icon to see them all).
- Finally, give them the URL to this page so they can see this information themselves