Even during this era of declining air traffic because of the COVID-19 pandemic, there are still thousands of airplanes flying on any given day throughout the United States and the world. These aircraft can range from commercial jets to general aviation and private planes to military jets of various armed forces. If you are an AvGeek (or even just curious), there are plenty of apps and websites that can help you figure out what the airplane you see overhead is, or even track a flight you’re on.

These services generally work by using a system that is based on Automatic Dependent Surveillance-Broadcast, or ADS-B, which is a satellite-based radio frequency system. Many aircraft are now equipped with ADS-B transmitters that share their location, aircraft type, and more with other airplanes and air traffic control. Because of this, a large number of websites and apps can now show you what is in the skies around you at any time.

Some of these tools are free, while others require a subscription to use all the features. In addition to the basic map that shows what planes are in the sky, some of these services offer more details on specific flights, including arrival and departure times, gate information, and any delays. Depending on the service, you can also sign up for email or text alerts that will keep you updated as flights change.

You can search for a specific flight by its identifier, such as the flight number or the airline’s name, or you can perform a more general search using the origin and destination airports, if you know them. You can also filter flights by type, status, air traffic control regions, and more. The resulting list of flights will then be displayed on the map. A premium version is available that allows you to search for more detail, such as the actual calibrated altitude and ground speed of each plane, and it offers more customization options.

Another great feature of this tool is that it works on any Apple device, from iPhones and iPads to the Apple Watch. And, because the Apple Watch has a built-in GPS chip, it can also be used to check on a flight without having to open an app or have a Wi-Fi connection.

Having the ability to track flights is especially handy when you’re traveling, either to make sure your flight will depart on time or to double-check its expected arrival time if you’re meeting someone at the airport. But it can also be useful when you’re simply watching the skies for a friend or family member’s plane. And of course, it’s a good way to know whether your luggage made it to its final destination. Just remember that the data on these websites and apps is not always accurate, and it can take a while for them to update. And, some airlines or locations may have asked these sites not to display their flights for any number of reasons.