Comparison

Eos Tools Pro vs GPS Diagnostic

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

Head to head
About

Eos Tools Pro

This utility app provides advanced GNSS information for high-precision receivers, crucial for GIS and surveying. It includes an NTRIP client for corrections, user-configurable alarms, and background operation with mapping software.

Highlights
  • Advanced GNSS information (RMS, PDOP, differential status)
  • Built-in NTRIP client for RTK/DGNSS corrections
  • User-configurable audible alarms
  • Background operation with mapping software
  • Satellite view for multiple constellations
  • Orthometric Height and Position Shift computation
Features
Read full description

Eos Tools Pro is a monitoring utility for the Arrow and Skadi series high precision GNSS receivers from Eos Positioning Systems. It provides advanced GNSS information such as RMS values, PDOP, differential status, satellites tracked and used, that are critical for submeter and centimeter GIS and surveying data collection. The app features a built-in end trip client to access RTK or DGNSS corrections from an RTK network. Eos Tools Pro also allows audible user configurable alarms and runs in the background of your mapping surveying software. Features: - Built-in NTRIP client to connect to an RTK Network - Displays GNSS and Tilt Compensation accuracy with quality control information - Select the Skadi Smart Handle mode: Extensible Virtual Range Pole™ or Invisible Range Pole™ - Satellite view for all constellations in use (GPS, GLONASS, BeiDou, QZSS and IRNSS) - User configurable alarms - Orthometric Height (Geoid models for vertical datum) - Compute and apply Position Shifts to accommodate different - Laser Offset Mapping for Esri ArcGIS® Field Maps - Locate and map underground utility assets directly in ArcGIS Field Maps - Terminal emulator to send configuration commands to the receiver - HTML5 built-in browser Disclaimer: "Continued use of Eos Tools Pro running in the background and connected to the GPS/GNSS receiver can dramatically decrease the battery life of your Apple device." Technical Support: For technical support, questions, feedback or bug reporting, please contact support@eos-gnss.com.

About

GPS Diagnostic

This app tests your device's GPS module, providing precise navigation parameters and diagnosing location issues. It supports multiple satellite systems and offers advanced coordinate conversions through an in-app purchase.

Highlights
  • Test GPS module
  • Fast GPS lock time
  • Precise navigation parameters
  • GPS "JumpStart" technology
  • Full satellite system support
  • Additional coordinate systems (IAP)
Features
Currently charting
Read full description

KEY FEATURES: - Essential tool for your iPhone & iPad. - Test the GPS module. - Fast GPS lock time. - Precise navigation parameters. - Supplements operation of your navigation apps. - GPS "JumpStart" technology. - If location cannot be determined then it diagnoses why. - Assists you in changing conditions to get a reliable location. - GPS, Galileo, GLONASS, QZSS full support. - Latitude & Longitude, and WGS84 included by default. - In-App Purchase: USNG, MGRS, UTM, OSNG, GEOREF, GARS & 174 Datums (free basic functionality). - **NEW** Smaller footprint (now only 35MBytes) - Free technical and customer support by email. -------------------------------------- OVERVIEW: - Lodestone Chart™ displays all essential GPS satellite information using a chart with only 4 bars. This dramatically simplifies the diagnostic process (Registered Copyright). - GPS "JumpStart" technology may resolve GPS problems with third-party navigation applications that have a frozen location, are slow to respond or are performing inaccurately. - Uses the internal GPS of your iPhone or iPad. - Includes a Speedometer, Altimeter and Compass. - Location and altitude ( best-in-class accuracy and reliability ) - Speed (SOG) and Course (COG). - Heading (i.e. Compass) with ability to turn on and off the manual compass calibration. -------------------------------------- IN-APP PURCHASE (IAP) = "COORDINATES-PRO"   This adds additional coordinate systems and datums to the app to let you accurately work with many paper maps and charts used by civilians, U.S. military and NATO forces for walking, sailing, and flying. The coordinate systems and datums included are: - United States National Grid (USNG) - Military Grid Reference System (MGRS) -Old and New - Universal Transverse Mercator (UTM) - Ordnance Survey National Grid (OSNG) for Great Britain - World Geographic Reference System (GEOREF) - Global Area Reference System (GARS) - 174 Datums (e.g. WGS84, NAD83, NAD27, WGS72, ED50, ED79, OSGB36 etc....). -------------------------------------- REVIEWS: - The developer is a professional software and hardware engineer working in the satellite space industry. He is a yachtmaster and pilot with a passion for navigation and Apple products. - Consistent 5 star reviews, see what users are saying: "Perfect Diagnostic Tool - This is the best app if you need to know the actual status of the internal GPS." "Great app for kick starting navigation apps - This app finds a position every time and then all other nav apps work." "Excellent application - This was a much needed application for iOS devices." “I love the app. It’s been great to have when buying a new phone from eBay to check that the GPS is working. I had to return 3 phones last time before I got one with operational GPS.” "Awesome, over used term but this app is - This app does what other developers said they could not do." -------------------------------------- MORE INFORMATION: - Hardware information - Accuracy of measurements shown for pro users. - Imperial, metric and nautical units. These are the most commonly used and most useful navigation units. All easily changeable from the screen in use. - Does not require internet access and does not use cellular data. - Essential tool for any power user. (e.g. navigators, yachtsmen, pilots, app developers) - Share your location by text message, email etc. The format contains all essential information for improved accuracy. - Works with Garmin Glo. - GPS Diagnostic™ is a professional GPS test and measurement utility for your iPhone and iPad.

Screenshots

Eos Tools Pro4 screens
GPS Diagnostic4 screens

Verdict

The call

The clearest difference is price: Eos Tools Pro at Free against GPS Diagnostic's $2.99. Eos Tools Pro also leads on in-app purchases (none vs 1). GPS Diagnostic's advantage is review sentiment (78% vs 38%) and ratings volume (553 vs 9). On rating, 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

Eos Tools Pro is free to download; GPS Diagnostic costs $2.99 up front. GPS Diagnostic sells 1 one-off in-app purchase. Eos Tools Pro asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.6 for Eos Tools Pro against 4.7 for GPS Diagnostic. That said, the two scores are not equally well evidenced: GPS Diagnostic has 553 ratings behind it against 9, so its average is the more settled of the two. Written reviews are what separate them: 38% of Eos Tools Pro's written reviews are positive against 78% of GPS Diagnostic's.

UpkeepUpdate frequency

Eos Tools Pro ships an update every 2 months, GPS Diagnostic every 3 weeks. Both last shipped on October 24, 2026.

Scorecard8 real differences · 3 level
Eos Tools Pro versus GPS Diagnostic: the parameters behind the verdict, then further details
ParameterEos Tools ProGPS Diagnostic
PriceFree — better$2.99
Rating4.6 (9 ratings)4.7 (553 ratings) — better
Positive reviews37.5% of reviews78.0% of reviews — better
Number of ratings9553 — better
Update frequencyEvery 2 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
Best chart rank—#29 — better
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.08.0 — better
Further details — not scored
Size36 MB34 MB
Age rating17+4+
DeveloperEos Positioning SystemsDavid Ryall

Customer experience

Eos Tools Pro

All ratings9 ratings
Positive88.9%
Neutral11.1%
Negative0.0%
Written reviews8 reviews
Positive37.5%
Neutral12.5%
Negative50.0%

GPS Diagnostic

All ratings546 ratings
Positive91.4%
Neutral3.1%
Negative5.5%
Written reviews209 reviews
Positive78.0%
Neutral3.8%
Negative18.2%

Bugs and requests

Eos Tools Pro

Not enough reviews yet to summarise bugs or requests.

GPS Diagnostic

Reported bugs

2 issues
  • Crashes on startup for some users
  • Fails to detect GPS signal on certain devices

Requested features

4 requests
  • Display number of satellites in view and locked
  • Expand satellite signal strength graph to show more satellites
  • Add support for landscape mode
  • Provide more detailed GPS information (e.g., HDOP, VDOP)

In-app purchases

None

Eos Tools Pro

No in-app purchases

1 purchases

GPS Diagnostic

One-time1
  • Coordinates-ProFree

Questions

Is Eos Tools Pro free?
Eos Tools Pro is free to download, with no in-app purchases.
Is GPS Diagnostic free?
GPS Diagnostic costs $2.99, and also offers in-app purchases.
Which has better reviews, Eos Tools Pro or GPS Diagnostic?
GPS Diagnostic is rated higher. Eos Tools Pro averages 4.6 out of 5 from 9 ratings, while GPS Diagnostic averages 4.7 from 553 ratings.
Do Eos Tools Pro or GPS Diagnostic have ads?
Neither Eos Tools Pro nor GPS Diagnostic shows ads.
Which is updated more often, Eos Tools Pro or GPS Diagnostic?
Eos Tools Pro ships an update every 2 months, and GPS Diagnostic every 3 weeks. Most recently, Eos Tools Pro was updated on October 24, 2026 and GPS Diagnostic on October 24, 2026.

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