1. Accurate Altimeter (Android)

One of the more popular options and also one of the best. Accurate Altimerer lets you measure your altitude on your phone with three different methods – all without an Internet connection. It uses satellite triangulation, ground elevation from a global elevation map, and a pressure sensor (if your device has one). Between those three, the accuracy is pretty solid. It tracks your past walks, presenting you with an elegant graph showing your past altitude movement and uses hiker-friendly maps that show contour lines, the names of relevant peaks and other vital information. The free version is ad-supported, but it’s nothing too obnoxious. Notes on its use:

Three different methods of altitude measurementHiking mapsOption to share pictures of location names and altitudes.

2. Altitude Using the Compass App (iOS)

The quickest way to get the altitude measurement on an iPhone is using the default Compass app. If your phone is able to connect to a satellite and get a good connection, the Compass app will show your exact location coordinates and altitude. Unfortunately, there’s no such app present in Android by default. Fortunately, there are multiple third-party apps to view your altitude. Usually their accuracy doesn’t vary much since they use the same method to calculate altitude, so you can use them as well. Notes on its use:

Integrated into iPhone – no need for third-party appsKey info at a glance, but the feature lacks detail

3. My Altitude (iOS/Android)

My Altitude is a complete solution for most of your altitude needs. You’ll get to see the altitude, coordinates, barometric pressure, water boiling point, weather – even NOAA data you can download to use the app offline. It doesn’t come with any tracking or graphing features but does have a tool that lets you take a photo with attached coordinates, altitude, and other details. My Altitude is available to download on both iOS and Android. Notes on its use:

Accurate calculation of altitudeBarometric pressure reported to be inaccurateGreat for record keeping

4. Altimeter & Altitude Widget (Android)

This app from DS Software (only on Android) uses location, barometer, and geospatial survey data to help you get accurate elevation and altitude readings. Plus it comes with an array of maps and a feature that allows you to record and graph your altitude trends. Being able to switch easily between elevation (the SRTM and USGS settings are both for elevation) and altitude (GPS and Bar) is a great feature, since comparing the two readings can help you get a sense of how accurate your altitude is. If you have an onboard barometer, the app also provides an array of calibration options, allowing you to get the data from the nearest airport or set it manually. Its level of detail, variety of elevation/altitude settings, and tracking features make it an excellent choice as a workhorse altimeter. Notes on its use:

Easily switch between elevation and altitudeUse land survey altitude valuesNice social features, like photo-sharing

5. Altimeter GPS – Hike & Trek (iOS)

This iOS app comes with the standard altimeter, barometer, and compass, plus a pedometer and journey tracker so you can visualize your distance and altitude changes. There’s even an SOS feature that can automatically send someone your location in an emergency. It’s the trip tracking that sets this app apart, though, as many iOS altimeters don’t come with that feature. Notes on its use:

Excellent journey-tracker featuresUI can be awkward

6. Altimeter Ler (Android)

This app’s design makes you feel like you’re in an airplane cockpit, but you can’t argue with the rich data you get out of it. Altimeter Ler (available on Android) gives you a full readout of your location and environmental conditions plus a variety of maps and good tracking features. It can calculate altitude based on both GPS and barometer readings and even tells you the estimated error of the GPS data you’re getting. It doesn’t have visualization tools to track your altitude changes or elevation data, but it comes with enough other features to make up for those shortfalls. Notes on its use:

Calculates altitude with GPS and barometerIntrusive ads in free version

7. Altimeter (Android)

EXA Tools’ altimeter for Android doesn’t provide much extra data, but its interface is easy to read, and its tracking feature might actually be one of the best on this list, thanks to its nicely-presented altitude-change graph. It comes with many ads (you can get rid of them by going premium), but they’re not unmanageable, and the app itself works well. Notes on its use:

Altitude-change graph is a great featureReports of crashing

1. What is the difference between altitude and elevation?

The terms “Altitude” and “Elevation” are usually used interchangeably, but there’s a major difference between the two. An “altitude” is the vertical measure from a specific datum or plane, which is mostly sea level. Hence, an altitude is your height from mean sea level (also known as 0 feet). On the other hand, “elevation” is generally used to specify the height to which something rises, such as ground level, a building, etc. Any height is measured above a specific ground elevation and is usually published on specific maps or charts. An example: the elevation of a specific landmark can be 700 feet above mean sea level. If you were at the exact location at a a height of 2000 feet, your altitude would be 2000 feet above mean sea level (MSL), but your height would be 1300 feet above ground level (AGL) (2000-700 = 1300 feet).

2. How does a phone measure altitude?

While your phone is able to measure altitude, if you know the elevation of the ground below, you can calculate your exact height above ground. The most important altitude measurement tool in your phone’s arsenal is the GNSS/GPS receiver. If your phone can find at least four satellites, with one directly overhead, you can usually get an altitude reading accurate to within 10 to 20 meters (35 to 70 feet). Having good satellite reception isn’t always guaranteed, though, and while GPS-based altitude works most of the time, it can still be subject to fairly large errors. That’s why many modern phones are also equipped with barometric pressure sensors (barometers). Because gravity pulls everything down towards the Earth, including the atmosphere, pressure gets lower as your altitude increases. Measuring this change helps your phone figure out how far up or down you’ve gone. Shifting weather can also affect atmospheric pressure, though, so most altimeter apps will try to get the most current pressure data from a nearby meteorological station. This gives the app something to compare the pressure changes to. Barometer-based altitude measurements can still work without a data connection, but you may have to calibrate it manually.

3. Should I just get a real altimeter?

If “ain’t no mountain high enough” is less of a song lyric and more of a life motto for you, you might have your eye on a non-phone altimeter. The good news is that this probably isn’t necessary to measure altitude if your phone has a decent GNSS chipset and a barometer, as tests have shown smartphones and altimeters to have roughly similar accuracy. What you probably need, though, is a good GPS app and maybe one that can be used offline. Another handy helper would be one of these pedometer apps. Image credit: Trilateracion