Comparison

Ohm's Law vs Ref Tools

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

Head to head
About

Ohm's Law

This utility app calculates electrical resistance, voltage, and current using Ohm's Law. It provides a quick and easy way to solve electrical formulas for various applications.

Highlights
  • Ohm's Law calculations
  • Voltage calculation
  • Current calculation
  • Resistance calculation
  • Electrical formula solver
Features
Read full description

Ohm's Law Calculator

About

Ref Tools

This app provides HVACR technicians with essential tools and information for field service. It includes refrigerant calculators, troubleshooting guides, product finders, and access to spare parts. Listen to educational podcasts to enhance your knowledge on the go.

Highlights
  • Refrigerant Slider for P/T calculations
  • Solenoid valve coil testing tool
  • Refrigeration system troubleshooting guide
  • Product data finder
  • Spare parts ordering
  • Low-GWP refrigerant comparison
  • TXV Superheat optimization
  • Educational podcasts
Features
Read full description

Get the guidance, support, information, and tools you need—on the job and in the field. Ref Tools is a free, powerful app that contains essential tools every HVACR technician needs in their digital toolbelt. Ref Tools offers a collection of useful air conditioning and refrigeration tools: Refrigerant Slider As a featured part of Ref Tools, you get all the features and functionality that made Refrigerant Slider a hit with millions of installers around the world. Quickly calculate pressure/temperature ratios and find essential information on over 80 refrigerants. Magnetic Tool Test and troubleshoot solenoid valve coils quickly and easily. Troubleshooter Get help diagnosing issues in refrigeration systems, so you can quickly identify symptoms and find recommended solutions. Product Finder Find extensive product-related data in one place. Search by product code number or product category to access and share product specifications, documentation, visuals, and more. Spare Parts Access and order an extensive list of Danfoss spare parts and service kits for air conditioning and refrigeration applications. Low-GWP Tool Find and compare climate-friendly refrigerants for retrofitting by checking compatibility with the TXV. TXV Superheat Tuner Optimize superheat in less than 15 minutes. Using advanced algorithms, TXV Superheat Tuner provides valve-specific adjustment recommendations. Podcasts The workday can be full and the road long, so Ref Tools also provides you with some educational entertainment. You can listen to podcasts, including the popular Chilling with Jens podcast, directly in the app. So, take a break and chill out a bit while learning something new about refrigeration. More about Refrigerant Slider Refrigerant Slider, now a part of Ref Tools, helps you quickly calculate the pressure-to-temperature ratio for more than 80 refrigerants, including natural refrigerants such as ammonia and transcritical CO2. Refrigerant Slider also provides you with information about each refrigerant, including Global Warming Potential (GWP) and Ozone Depleting Potential (ODP). You can switch between the IPCC AR4 and AR5 values, where AR4 values are used in relation to the European F-Gas regulations. Refrigerant Slider’s P/T calculations use extended curve–fitting models based on Refprop 10 results. You can also see both dew and bubble point for refrigerants with glide. Streamline your workflow Ref Tools goes beyond just providing quick access to helpful tools; it helps you save time by allowing you to track your most visited service sites and save unique settings for each one. Simplify each service call with ease. Feedback Your input matters – we would love to hear it from you. We're committed to continuously improving Ref Tools to meet your needs. If you encounter a bug or have a feature suggestion, please use the in-app feedback function available in Settings. Alternatively, you can reach us via email at coolapp@danfoss.com. Danfoss Climate Solutions At Danfoss Climate Solutions, we engineer energy-efficient solutions to help the world get more out of less. Our innovative products and solutions enable a decarbonized, digital, and more sustainable tomorrow, and our technology supports a cost-efficient transition to renewable energy sources. With a strong foundation in quality, people, and the climate, we drive the energy, refrigerant, and food system transitions needed to achieve climate goals. Read more about us at www.danfoss.com. Terms and Conditions apply for use of the app.

Screenshots

Ohm's Law1 screens
Ref Tools4 screens

Verdict

The call

The clearest difference is rating: Ohm's Law at 4.7 against Ref Tools's 3.9. Ohm's Law also leads on review sentiment (81% vs 58%) and ratings volume (165 vs 52). Ref Tools's advantage is in-app purchases (none vs 1) and update cadence (every 5 weeks vs every 4 months). On price, 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

Both are free to download. Ohm's Law sells 1 one-off in-app purchase. Ref Tools asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Ohm's Law holds the better App Store score, 4.7 against 3.9. Both are backed by a comparable volume of ratings — 165 and 52 respectively. Written reviews point the same way: 81% of Ohm's Law's written reviews are positive against 58% of Ref Tools's.

UpkeepUpdate frequency

Ohm's Law ships an update every 4 months, Ref Tools every 5 weeks. The most recent releases landed on October 13, 2026 and October 7, 2026 respectively.

Scorecard7 real differences · 3 level
Ohm's Law versus Ref Tools: the parameters behind the verdict, then further details
ParameterOhm's LawRef Tools
PriceFreeFree
Rating4.7 (165 ratings) — better3.9 (52 ratings)
Positive reviews80.7% of reviews — better57.6% of reviews
Number of ratings165 — better52
Update frequencyEvery 4 monthsEvery 5 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS9.0 — better15.0
Further details — not scored
Size9 MB98 MB
Age rating4+4+
DeveloperCreature Code Mobile, LLCDanfoss A/S

Customer experience

Ohm's Law

All ratings165 ratings
Positive93.3%
Neutral0.6%
Negative6.1%
Written reviews109 reviews
Positive80.7%
Neutral3.7%
Negative15.6%

Ref Tools

All ratings52 ratings
Positive73.1%
Neutral3.8%
Negative23.1%
Written reviews66 reviews
Positive57.6%
Neutral7.6%
Negative34.8%

User reviews

Ohm's Law

From 165 App Store ratings

What we love

  • 👍 Extremely user-friendly and intuitive interface
  • ⚡ Fast and accurate calculations
  • 🎯 Simple, focused design with no unnecessary clutter
  • 💰 Free app with minimal ads that don't interfere
  • 🔧 Requires only two values to calculate the rest

Room to improve

  • 🐛 Crashes when entering decimal values in multiple fields
  • 🐛 Reset function doesn't work properly after first use
  • ⚠️ App incompatible with newer iOS versions
  • ⚠️ Outdated and hasn't been updated since iOS 6
  • ❌ Limited functionality - single resistor only

Ref Tools

From 52 App Store ratings

What we love

  • 👍 Useful tool for HVAC/R techs
  • 👍 Great idea for an app
  • 👍 Best refrigeration and hvac app
  • 👍 Useful App for HVACR
  • 👍 Brilliant app

Room to improve

  • 🐛 Crashes instantly on launch
  • 🐛 App won’t open on iPhone
  • 🐛 Flashes up and disappears
  • 🐛 Cannot open app
  • 🐛 Immediately shuts off

Bugs and requests

Ohm's Law

Reported bugs

8 issues
  • App crashes when entering decimal points in multiple fields simultaneously
  • Reset button fails to clear values after first use
  • Large calculations cause app to crash
  • Crashes on iPhone SE and iPhone 7 Plus with iOS 10+
  • App won't open or frequently crashes on some devices
Show 3 more
  • Crashes when entering ohms values
  • Decimal point entry causes immediate crash on certain devices
  • App unstable and incompatible with iOS 10 and later versions

Requested features

9 requests
  • AC/DC checkbox option
  • Three-phase power calculations
  • Parallel and combination circuit support
  • Impedance and reactance calculations
  • Ohm's Wheel reference tool
Show 4 more
  • Useful electrical tables
  • Example calculations showing work/formula
  • Number pad input instead of full keyboard
  • iOS compatibility updates for newer versions

Ref Tools

Reported bugs

27 issues
  • CRASHED instantly on Mac Mini M4
  • App won’t open on iPhone
  • App flashes up and disappears
  • Cannot open app
  • Immediately shuts off since recent release
Show 22 more
  • Crash au lancement since update
  • Will not save to Home Screen
  • Incorrect PT Charting for r134a
  • Information doesn’t slide down
  • Crashes on iOS12.1.4
  • App won’t open since previous update
  • List of refrigerants shifted upwards on iPhone 10
  • Stuck on R134a, needs update for current iOS
  • R744A only goes to 60 psi
  • Scale did not go low enough for deep vacuum
  • Missing R22 on Apple version
  • Missing R717 (Ammonia)
  • Missing R-22
  • Missing R124a
  • No longer lists Ammonia
  • Missing Refrigerants since app update
  • Missing Ammonia and CO2
  • r410a is missing since update
  • Removed r22, 410a, and 407c
  • Refrigerants missing now
  • Removed slider for ammonia
  • Scale doesn't go into vacuum

Requested features

18 requests
  • More residential AC information
  • Troubleshooter for Residential & Commercial
  • Add SP22 refrigerant
  • Add R-11 refrigerant
  • Add R-123 range down to 40 degrees
Show 13 more
  • Add R744 and R744A to 0 psia
  • Scale to go lower for R-123 vacuum
  • Add R410a
  • Add R407c
  • Add R404A
  • Add R22
  • Add R124a
  • Add Ammonia
  • Add CO2
  • Add R717 (Ammonia)
  • Scale going higher on CO2
  • Setting for high altitude
  • Scale to go into vacuum

In-app purchases

1 purchases

Ohm's Law

One-time1
  • Remove Ads$0.99
None

Ref Tools

No in-app purchases

Questions

Is Ohm's Law free?
Ohm's Law is free to download, with in-app purchases available.
Is Ref Tools free?
Ref Tools is free to download, with no in-app purchases.
Which has better reviews, Ohm's Law or Ref Tools?
Ohm's Law is rated higher. Ohm's Law averages 4.7 out of 5 from 165 ratings, while Ref Tools averages 3.9 from 52 ratings.
Do Ohm's Law or Ref Tools have ads?
Neither Ohm's Law nor Ref Tools shows ads.
Which is updated more often, Ohm's Law or Ref Tools?
Ohm's Law ships an update every 4 months, and Ref Tools every 5 weeks. Most recently, Ohm's Law was updated on October 13, 2026 and Ref Tools on October 7, 2026.

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