What to Look for in a Space Station Tracker
There are a lot of satellite tracking apps on the market, but most of them are built for radio operators or satellite hobbyists. If what you actually care about is following the people inside the space stations, your needs are a bit more specific. Before we get into individual apps, here is what separates a good space station tracker from a generic orbital tool.
Pass predictions with sky maps. A pass prediction tells you when a space station will be visible from your location, including the time, direction, and brightness. The best apps overlay this on a sky map or augmented reality view so you know exactly where to point. Timing matters: even a few seconds off and you might look the wrong way while the station glides past behind you.
Support for both the ISS and Tiangong. There are two crewed space stations in orbit right now, and Tiangong is just as bright as the ISS under the right conditions. An app that only tracks the ISS is leaving out half the picture. The best trackers handle both, with separate predictions for each.
Crew information. This is the piece that most generic satellite trackers miss entirely. If you want to know how many people are in space right now and who they are, you need an app that pulls crew data and links it to the station you are watching. Knowing that there are seven people aboard the bright dot crossing your sky makes the experience feel very different from just watching an unnamed object go by.
Push notifications for visible passes. The best passes only last a few minutes, and they do not happen every night. A good tracker sends you a notification before a bright pass so you can step outside without having to check the app manually every evening. The notification should include the time, direction, and expected brightness so you can decide at a glance if it is worth going out.
Real-time position on a map. Being able to open an app and see exactly where the ISS or Tiangong is right now, plotted on a world map, is satisfying in a way that raw orbital numbers are not. Some apps update this position every second using live telemetry, while others refresh less frequently. For casual use, either works fine.
Ease of use. Some apps bury useful features under layers of settings and jargon. The best ones put pass times and maps front and center, with more advanced data available if you want to dig deeper. If you need to read a tutorial before you can find tonight's ISS pass, the app has a design problem.
NASA Spot the Station
NASA's Spot the Station is the simplest way to get ISS pass alerts, and it comes from the people who actually run the station. It is a website, not a mobile app. You visit spotthestation.nasa.gov, enter your location, and sign up for email or text message alerts. When a visible ISS pass is coming up for your area, NASA sends you a notification with the time, duration, and direction to look.
The strengths here are reliability and simplicity. The data comes directly from NASA's trajectory calculations, and the signup process takes about thirty seconds. There is no app to install, no account to create beyond your email or phone number, and no settings to configure. You just start getting alerts.
The limitations are equally clear. Spot the Station only covers the ISS. There is no Tiangong tracking, no crew information, no real-time map, and no sky chart showing you where to look. If you want any of those features, you need a separate tool. The alerts are also email or text only, so there is no push notification with a countdown or interactive map.
For someone who just wants to be told when to go outside and look up, Spot the Station is perfectly adequate. It does one thing and does it well. But if you are reading this roundup, you probably want more than that.
Skytrail
Skytrail is an iOS app for tracking satellites and space stations, and it has been my daily driver for station tracking for over a year now. Where it stands out most clearly is crew tracking. The app shows real-time crew information for both the ISS and Tiangong, so when you pull up either station you can see the names and details of every person currently aboard. For the purposes of this roundup, which is specifically about tracking the people in space, that is a meaningful differentiator.
Beyond crew data, Skytrail provides pass predictions with an augmented reality sky view. You point your phone at the sky and the app overlays the predicted path of the station, making it straightforward to know exactly where to look. I have tested the pass predictions against actual observations dozens of times from my yard in Colorado, and the timing has been dead-on accurate every single time. It also tracks thousands of other satellites if you are interested in objects beyond the two crewed stations.
The interface is clean and modern, with a dark design that works well for nighttime use (which is when you will be doing most of your observing). Real-time position tracking shows both stations on a map, and push notifications alert you before visible passes. What I appreciate most is how Skytrail ties everything together: you get the notification, open the app, see who is aboard, and point your phone at the sky to find the station. The whole flow feels like it was designed by someone who actually goes outside and watches passes, not just someone who knows orbital mechanics.
Skytrail is iOS only, which obviously limits its audience. If you are on Android, you will need to look at the other options in this list. But if you are on iPhone, this is the app I recommend first. Being able to see who is aboard each station, right alongside your pass predictions, adds a human dimension that most satellite trackers lack. That combination of crew data, accurate predictions, and a thoughtful interface is why it has stayed on my home screen.
ISS Detector
ISS Detector has been around for years and has built a loyal following, particularly on Android (where it started) though it is now available on iOS as well. As the name suggests, it began as a dedicated ISS tracker, but it has expanded over time to cover Tiangong, the Hubble Space Telescope, and various other bright satellites.
The core experience revolves around pass predictions and a sky radar view. The radar shows you a compass-style display with the station's predicted path overlaid on it, so you can orient yourself without needing to hold your phone up to the sky. Notifications are reliable, arriving a few minutes before each pass with the key details: start time, maximum elevation, and direction.
ISS Detector uses a freemium model. The base app is free and ad-supported, with a paid pro version that unlocks additional features like Tiangong tracking and removes the ads. The free version covers ISS passes well enough for most people, and the pro upgrade is reasonably priced if you decide you want the extras.
One area where ISS Detector falls short is crew information. It is fundamentally a satellite tracking tool rather than an astronaut tracking tool. You get orbital data and pass times, but not a list of who is aboard. If knowing the crew is important to you, you will want to supplement it with another source. That said, for pure pass prediction reliability, ISS Detector has years of proven track record and a large user community.
Heavens-Above
Heavens-Above is the tool that experienced satellite observers have relied on for decades. Originally a website (heavens-above.com), it now also has an Android app. It provides extremely detailed astronomical data, including satellite passes, Iridium flares (from older Iridium satellites), and comprehensive star charts.
For space station tracking, Heavens-Above gives you pass predictions with predicted magnitude (brightness), trajectory plotted on a star chart with constellation backgrounds, and altitude/azimuth data at multiple points along the pass. If you want to know that the ISS will reach magnitude -3.8 as it passes through Cassiopeia at 42 degrees elevation, this is your tool. It covers both the ISS and Tiangong, along with hundreds of other trackable objects.
The tradeoff is the interface. Heavens-Above was designed for people who already know what right ascension and declination mean. The website looks like it was built in the early 2000s (because it was), and the Android app, while functional, does not feel particularly modern. There is no augmented reality view, no push notifications on the website, and no crew information. It is a tool built by astronomers for astronomers.
If you have some experience with stargazing and want the most precise pass data available, Heavens-Above is excellent. It is completely free, with no ads or premium tier. But if you are new to satellite observing, the learning curve can be steep. You might get more out of starting with a simpler app and coming back to Heavens-Above once you are comfortable with the basics. For help with your first sighting, our guide on how to see the space station from your backyard walks through the process step by step.
Orbitrack
Orbitrack is an iOS app that takes a more visual approach to satellite tracking. Its centerpiece is a 3D globe view that shows satellites orbiting in real time, with smooth animations and orbit path visualization. You can spin the globe, zoom in on specific regions, and watch satellites trace their ground tracks across the surface.
For pass predictions, Orbitrack provides a list of upcoming visible passes with start/end times, maximum elevation, and brightness estimates. The 3D view makes it easy to understand why certain passes are visible and others are not, since you can see the satellite's position relative to the sunlight terminator and your location on the globe.
The app covers a wide catalog of satellites, including both the ISS and Tiangong. Real-time position data updates continuously, and the visualization is genuinely enjoyable to watch even when you are not planning an observation. It is the kind of app you might open just to see where the ISS is right now, because the globe view makes that information feel tangible.
Orbitrack is a paid app with no free tier, which is worth considering against the free or freemium alternatives on this list. It also does not include crew information, so like ISS Detector and Heavens-Above, it focuses on the orbital mechanics side rather than the human side. The 3D visualization is its strongest selling point, and if that appeals to you, it delivers.
Comparison Table
Here is a side-by-side look at how these five options stack up on the features that matter most for tracking astronauts and space stations.
| App | Platform | ISS Tracking | Tiangong Tracking | Crew Info | Notifications | Price |
|---|---|---|---|---|---|---|
| NASA Spot the Station | Web | Yes | No | No | Email/SMS | Free |
| Skytrail | iOS | Yes | Yes | Yes | Push | Free |
| ISS Detector | Android, iOS | Yes | Yes (Pro) | No | Push | Free / Paid Pro |
| Heavens-Above | Web, Android | Yes | Yes | No | No | Free |
| Orbitrack | iOS | Yes | Yes | No | Push | Paid |
Which App Should You Use?
The right choice depends on what you care about most, but I will lead with my overall pick. If I had to recommend just one app, it would be Skytrail. The crew tracking alone makes it worth it, and the pass predictions have been dead-on accurate every time I have used them. It does the most important things really well: it tells you when to look, shows you where to point, and tells you who is up there. For most people reading this site, that combination is exactly what you want. Here is the full breakdown by use case.
If you just want ISS pass alerts with zero setup: go with NASA Spot the Station. Sign up with your email, get alerts, go outside when told. No app needed, no learning curve. It is the fastest way to start seeing the station, and the data comes straight from NASA. I still have my Spot the Station alerts active even though I primarily use Skytrail, just as a backup.
If you want crew tracking and both stations covered: Skytrail is the clear winner. It is the only option on this list that shows you who is aboard each station alongside your pass predictions. If knowing the names and backgrounds of the people overhead matters to you (and given that you are reading a site called Humans in Space, it probably does), nothing else comes close. This is the app I open every evening before heading out to my backyard.
If you want the most technical and detailed pass data: Heavens-Above gives you magnitude predictions, star chart overlays, and the kind of precision data that experienced observers want. It is not the friendliest interface, but the depth of information is unmatched. I use it occasionally when I want exact magnitude predictions for a specific pass, but for day-to-day tracking Skytrail covers what I need.
If you want a polished 3D visualization: Orbitrack turns satellite tracking into something visually engaging. The globe view is the best in any consumer app, and it makes orbital mechanics intuitive. Worth the price if you enjoy that style of presentation.
If you are on Android: ISS Detector is your best bet. It has been the go-to Android satellite tracker for years, with reliable notifications and solid pass predictions. The pro version adds Tiangong and removes ads. Heavens-Above is also available on Android if you want a more technical alternative.
Every app on this list does something well, and several of them are free, so it costs nothing to try a few and see what clicks. But if you want my honest take after spending a lot of evenings outside with all of these tools: Skytrail is the one that stuck. It gets the balance right between useful data and a clean experience, and the crew tracking makes every pass feel more personal.