Comparison

Sentron vs ColorMetric

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

Head to head
About

Sentron

Transform your mobile device into a sophisticated pH meter. Connect wirelessly to specialized probes for accurate measurements in various applications. The app guides you through calibration, data logging, and export.

Highlights
  • Wireless pH/EC measurement
  • Bluetooth probe connectivity
  • Step-by-step calibration
  • Data logging and graphing
  • GPS data mapping
  • Automatic temperature compensation
Read full description

Turn your mobile device into a full-featured pH meter by downloading this free Analytical Sensors app. Connect your device to one or more non-glass Sentron pH probes with Bluetooth Low Energy technology. Step-by-step instructions included. The app is intuitive and guides you through the complete process of setting configurations, calibrating, acquiring, storing and exporting all measurement data. Monitoring pH was never that easy! SENTRON EUROPE BV Sentron has developed a comprehensive line of wireless high-quality probes for glass-free pH measurements. Sentron’s ISFET pH sensor technology provides accurate and reliable pH measurements for various applications. All pH probes include a replaceable, interchangeable sensor part for extra durability. It is wirelessly connected via Bluetooth to our Sentron app. Interested? Purchase your pH probe of interest simply at our web shop at www.sentron.nl/shop . For your convenience we offer carry cases with a buffer set and predrill stick. This predrill stick can be used to prepare pilot holes in dry soils. The carry case offers convenient protection for your probes. pH AS A CRITICAL PARAMETER pH is a critical parameter in many areas. Examples include agriculture, horticulture, environment, laboratory applications and inline food processes for beer, wine, meat, fish, or cheese. SENTRON’S ISFET pH SENSOR PROBE * Wireless * Glass-free * Robust * Dry storage SENTRON GLASS-FREE pH PROBES Thanks to comprehensive ISFET pH sensor technology, Sentron offers glass-free wireless pH probes. The probes are used for accurate and reliable pH measurements for demanding applications. Multiple Sentron probes can be connected simultaneously. Functions include calibration (1-, 2-, 3- and 5-point calibration), sample measurement, data logging, graph plotting and data sharing. Measurement of pH and temperature starts as soon as the probe is connected to the mobile device. A notification signals when a probe needs a new calibration. The measurement can be displayed as tabulated data or a graph. ADDITIONAL FEATURES * Display of the probe’s condition, name, reading stability and battery life * Both automatic customizable and manual data logging * Automatic temperature compensation (ATC) * User-definable alarm thresholds for pH and temperature * Automatic recognition of previously connected probes and calibration data stored on probes * GPS mapping of your pH data * Advanced mode option for expert users WIRELESS The Sentron probe’s Bluetooth Low Energy technology offers many advantages in wireless measurement convenience. Each probe can be used up to 50 meters (150 feet) from the mobile device. The Sentron probe and app are ideal for professionals and private indiiduals that need accurate wireless measurements in the laboratory, industry halls, outdoors, etc. Sentron probes are compatible with devices with Bluetooth 5.0 or higher. DEMO PROBES AVAILABLE Would you like to experience our app before buying our product? That’s possible! Download the app and add the virtual demo probe in the app. Experience the convenience of the app yourself. COMING SOON: MULTIPARAMETER PROBE The current pH probe portfolio will be extended with probes for EC (Electrical Conductivity) and ORP (Oxidation Reduction Potential). Imagine: alle these parameters in one and the same probe! Follow us at www.sentron.nl for any related news.

About

ColorMetric

Features
Read full description

Water Testing, Perfected for Your Eyes and Your Environment. Are you tired of squinting at paper charts trying to decide if your Nitrate is 10 or 20? ColorMetric transforms your iPhone into a professional-grade colorimeter. Designed for both freshwater enthusiasts and reef-keepers, our app eliminates the subjectivity of traditional testing. What makes ColorMetric different? Intelligent Lighting Calibration: Room lighting often distorts colors. ColorMetric allows you to calibrate the app to your specific environment, ensuring your camera "sees" the same color every time, regardless of whether you’re under LEDs or sunlight. Individual Card Calibration: Every test kit brand has slight variations. You can calibrate the app to your specific test cards for unparalleled accuracy. Guided Test Assistant: Never botch a 5-minute wait again. The app walks you through every step of the testing process with integrated timers and clear instructions for every parameter. Dual Environment Support: Specialized profiles for Saltwater and Freshwater aquariums, covering everything from pH and Ammonia to high-sensitivity Reef parameters like Phosphate and Magnesium. A Healthier Tank Starts with Better Data Accuracy is the difference between a thriving ecosystem and a crash. ColorMetric bridges the gap between affordable liquid tests and expensive digital monitors, giving you the precision you need at a fraction of the cost. Download ColorMetric today and stop guessing. Privacy Policy URL: https://colormeter.web.app/privacy-policy.html Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Sentron4 screens
ColorMetric4 screens

Verdict

The call

The clearest difference is in-app purchases: Sentron at none against ColorMetric's 1. Sentron also leads on device support (3 vs 1) and iOS requirement (15.0 vs 17.0). ColorMetric's advantage is update cadence (weekly vs every 5 weeks). On price and ads 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

Both are free to download. ColorMetric sells 1 in-app purchase, starting at $9.99 per year. Sentron asks for nothing beyond the download.

UpkeepUpdate frequency

Sentron ships an update every 5 weeks, ColorMetric weekly. The most recent releases landed on September 22, 2026 and September 9, 2026 respectively.

Scorecard4 real differences · 5 level
Sentron versus ColorMetric: the parameters behind the verdict, then further details
ParameterSentronColorMetric
PriceFreeFree
Rating3.0 (2 ratings) — better—
Number of ratings2 — better—
Update frequencyEvery 5 weeksWeekly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS15.0 — better17.0
Further details — not scored
Size94 MB6 MB
Age rating4+4+
DeveloperSentron Europe B.V.Lance Zukel

In-app purchases

None

Sentron

No in-app purchases

1 purchases

ColorMetric

Subscriptions1
  • ColorMetric Annual Ad Free$9.991 Year

Questions

Is Sentron free?
Sentron is free to download, with no in-app purchases.
Is ColorMetric free?
ColorMetric is free to download, with in-app purchases available.
Do Sentron or ColorMetric have ads?
Neither Sentron nor ColorMetric shows ads.
Which is updated more often, Sentron or ColorMetric?
Sentron ships an update every 5 weeks, and ColorMetric weekly. Most recently, Sentron was updated on September 22, 2026 and ColorMetric on September 9, 2026.

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