Comparison

Theodolite HD vs Earthmate

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Theodolite HD

This app combines a compass, inclinometer, rangefinder, GPS, and map for augmented reality navigation. It allows users to capture data-overlay photos and videos, view positions on a map with offline options, and share location data with others. It's designed for professional use and outdoor activities.

Highlights
  • Augmented reality viewfinder
  • Compass and inclinometer
  • GPS and map with offline options
  • Data-overlay photo/video camera
  • Rangefinder and nav calculator
  • Location sharing and team tracking
Read full description

Theodolite HD is a multi-function viewfinder that combines a compass, two-axis inclinometer, rangefinder, GPS, map, nav calculator, and geo-overlay photo/movie camera into one indispensable app. Theodolite was one of the very first augmented reality (AR) apps when it was released in 2009, and it’s been downloaded and used by millions of customers since then. Uses are endless, and the app is great for land measurements, outdoor sports, sightseeing, navigation, and finding your way around. Theodolite is a pro grade app and is used extensively by surveyors, geologists, architects, engineers, competitive sportsmen, first responders, military personnel, and search and rescue workers around the world. Theodolite lets you take data-overlay photos and movies with 2X-8X zoom. Overlay geographical data, angle markings, date/time, author/company info, and project notes directly on photos and movies for later reference. The same data is written into the metadata record of images, making image files self-contained data records. Third-party apps can tap into Theodolite's advanced camera functions with a camera sharing feature. View current position on the built-in map with optional offline Outdoors maps that include topo contours, roads, trails, landmarks, campgrounds, ski lifts, and more. Live map markers continually update distance/heading relative to the current location and also show wayfinding info in the main viewfinder. Draw polygons on the map to mark things like property boundaries and trails, and import/export polygon data via KML. Share map markers and nav calculator points with other users of Theodolite via text messages or e-mail. This powerful capability opens up a wide range of collaborative uses including team land surveying, accident investigations, spotting wild fires, triangulation of landmarks, and advanced tactical observation and targeting. With an optional in-app purchase to enable team tracking, you can share location with up to 20 people on Theodolite's map. Theodolite includes features for serious users like a reference angle mode, nav calculator, map marker import/export, manual and automatic data logging with CSV and KML export, clipboard integration, %grade display, mil compass readout, optical rangefinders (including a mil-based reticle, sniper-style stadiametric graphs, and a variable 4X-24X scope), and night filters to improve use in dark conditions. Theodolite can provide location in military grid reference system (MGRS) coordinates, Universal Transverse Mercator (UTM) coordinates, British/Irish National Grids, US National Grid, Maidenhead locator system, Map Grid of Australia, and six latitude/longitude formats. Optional US State Plane coordinates include SPCS27 and SPCS83 zones covering all US States. The optional Datum Pack adds over 230 geodetic datums to the app to improve position computation from GPS data, covering regions and countries on all continents around the world. AR Layers include navigational aids like the sun, moon, planets, and Polaris (North star), and the optional US Mountain Summits layer that shows over 70,000 US mountain summits in the viewfinder. Theodolite has been shown in Apple Keynotes, featured on the App Store, and has been a #1 selling Navigation app in App Stores around the world. Since its introduction in 2009, Theodolite has defined augmented reality navigation. The app continually introduces new technologies, pushing the limits of iOS app development and taking advantage of new hardware capabilities. Find out why Apple named Theodolite one of the most amazing apps available and showed it being used to explore the Great Wall of China. Where will you take it on your next adventure? Note: Theodolite HD is an iPad app -- see the regular “Theodolite” app for use on an iPhone or iPod Touch. And be sure to check out the all-new "Theodolite for Watch" and put Theodolite on your wrist!

About

Earthmate

Connect your satellite communicator to your mobile device for text messaging, navigation, and trip planning. Access offline maps, track your location, and share your adventures globally. Stay connected and safe on any outdoor expedition.

Highlights
  • Send/receive text messages
  • Offline topographic maps
  • Waypoint and route navigation
  • Tracking and location sharing
  • Trip logging and planning
  • Cloud storage for trips
  • Control inReach device features
Read full description

Pair your inReach® satellite communication device with the Earthmate® app to get all the features you need to send and receive text messages, navigate and stay connected during your outdoor adventures. It’s perfect for planning, tracking and sharing your trip anywhere around the globe. This Garmin application lets you access¹: • Unlimited topographic maps that you can cache on your device and store for offline use, including topographic maps and quad sheets • Aerial imagery • Hybrid maps • Waypoints and route navigation • Tracking and location sharing • High-detail GPS trip logging • Unlimited cloud storage of routes, waypoints and tracks • Online trip planning • Control and access all the features of your inReach device from the app: send 2-way custom or preset text and email messages, trigger an SOS from anywhere in the world, track your location and more By pairing your mobile device (via Bluetooth® technology) with inReach, the Earthmate app turns your mobile device into a true satellite communication, GPS navigation and safety tool. To access the 100% global Iridium® satellite network for live tracking and messaging – including SOS capabilities – from the Earthmate app, an inReach device with active satellite subscription is required. You can plan your adventures from your account on the Garmin Explore™ website, wirelessly sync them to your smartphone or tablet, and then save all your trip data and maps with unlimited cloud storage. With the use of the LiveTrack™ feature, loved ones can follow your location in real time² and see data such as distance, time and elevation. Learn more about inReach devices and technology at www.garmin.com/inreach. Continued use of GPS running in the background can dramatically decrease battery life. Don't forget to stop tracking. ¹Access varies by model. ²When used with your compatible smartphone and the Earthmate® app or when used with your compatible inReach-enabled Garmin device.

Screenshots

Earthmate4 screens

Verdict

The call

The clearest difference is review sentiment: Theodolite HD at 91% against Earthmate's 22%. Theodolite HD also leads on rating (4.7 vs 2.6) and iOS requirement (15.6 vs 17.0). Earthmate's advantage is price (Free vs $8.99) and in-app purchases (none vs 8). On ratings volume, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Earthmate is free to download; Theodolite HD costs $8.99 up front. Theodolite HD sells 8 one-off in-app purchases. Earthmate asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Theodolite HD holds the better App Store score, 4.7 against 2.6. Both are backed by a comparable volume of ratings — 136 and 273 respectively. Written reviews point the same way: 91% of Theodolite HD's written reviews are positive against 22% of Earthmate's.

UpkeepUpdate frequency

Theodolite HD ships an update every 4 months, Earthmate monthly. The most recent releases landed on October 23, 2026 and October 29, 2026 respectively.

Scorecard7 real differences · 3 level
Theodolite HD versus Earthmate: the parameters behind the verdict, then further details
ParameterTheodolite HDEarthmate
Price$8.99Free — better
Rating4.7 (136 ratings) — better2.6 (273 ratings)
Positive reviews91.4% of reviews — better21.6% of reviews
Number of ratings136273 — better
Update frequencyEvery 4 monthsMonthly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPadiPhone, iPad — better
Requires iOS15.6 — better17.0
Further details — not scored
Size30 MB92 MB
Age rating4+12+
DeveloperCraig HunterGarmin

Customer experience

Theodolite HD

All ratings136 ratings
Positive94.1%
Neutral2.2%
Negative3.7%
Written reviews185 reviews
Positive91.4%
Neutral3.2%
Negative5.4%

Earthmate

All ratings273 ratings
Positive33.0%
Neutral15.0%
Negative52.0%
Written reviews153 reviews
Positive21.6%
Neutral19.0%
Negative59.5%

User reviews

Theodolite HD

From 136 App Store ratings

What we love

  • 🚀 Intuitive and easy to use
  • 🔍 Accurate measurements and data
  • 📷 Useful photo documentation features
  • 🧭 Versatile for various applications
  • 🏫 Great for educational and teaching purposes

Room to improve

  • 🔍 Occasional compass/sensor accuracy issues
  • 💰 Expensive in-app purchases for maps and features
  • 📱 Separate iPhone and iPad versions require double purchase
  • 🔄 Lack of screen rotation support on some devices

Earthmate

From 273 App Store ratings

What we love

  • 🚀 Offline maps
  • 📡 Satellite communication
  • 💬 Messaging functionality
  • 🗺️ Tracking and navigation

Room to improve

  • 🐛 Unreliable Bluetooth connectivity
  • 🔍 Lacking detailed maps
  • 🔑 Login/sync issues
  • 🔧 Buggy and unstable
  • 🗓️ Frequent app crashes

Bugs and requests

Theodolite HD

Reported bugs

2 issues
  • Occasional crashes or freezes, especially on older devices
  • Camera orientation issues on some devices

Requested features

4 requests
  • Add option to set elevation angle to 0 degrees horizontal
  • Implement cross-device sync and data sharing
  • Expand map coverage and reduce in-app purchase costs
  • Add support for more camera features like video recording

Earthmate

Reported bugs

5 issues
  • Invisible text fields
  • Disappearing waypoints and tracks
  • Inability to send preset messages from app
  • Incorrect wind speed display
  • Broken map downloads

Requested features

5 requests
  • Apple Watch integration
  • Customizable preset messages
  • Improved map detail and customization
  • Seamless sync between app and device
  • Frequent message check intervals

In-app purchases

8 purchases

Theodolite HD

One-time8
  • 1,000 Outdoors Map Tiles$0.99
  • Team Tracking$1.99
  • World Datum Pack$2.99
Show 5 more
  • US Mountain Summits AR Layer$2.99
  • 5,000 Outdoors Map Tiles$4.99
  • 10,000 Outdoors Map Tiles$8.99
  • 20,000 Outdoors Map Tiles$17.99
  • US State Plane Coordinates$24.99
None

Earthmate

No in-app purchases

Questions

Is Theodolite HD free?
Theodolite HD costs $8.99, and also offers in-app purchases.
Is Earthmate free?
Earthmate is free to download, with no in-app purchases.
Which has better reviews, Theodolite HD or Earthmate?
Theodolite HD is rated higher. Theodolite HD averages 4.7 out of 5 from 136 ratings, while Earthmate averages 2.6 from 273 ratings.
Do Theodolite HD or Earthmate have ads?
Neither Theodolite HD nor Earthmate shows ads.
Which is updated more often, Theodolite HD or Earthmate?
Theodolite HD ships an update every 4 months, and Earthmate monthly. Most recently, Theodolite HD was updated on October 23, 2026 and Earthmate on October 29, 2026.

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