Comparison

RGB Test vs ChangeUnits2

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

Head to head
About

RGB Test

Features
Read full description

RGB Test is a simple and effective app for testing the screen of your iPhone or iPad. It quickly detects dead pixels and checks the accuracy of RGB color display. App Features: Full-screen color tests – red, green, blue, white, black, and more Fast detection of damaged pixels Intuitive interface – test your screen in just a few seconds Contrast check – compare text color against the background Download RGB Test and make sure your screen is working perfectly! RGB Test to prosta i skuteczna aplikacja do testowania ekranu Twojego iPhone’a lub iPada. Pozwala szybko wykryć martwe piksele oraz sprawdzić poprawność wyświetlania kolorów RGB. Funkcje aplikacji: Pełnoekranowe testy kolorów – czerwony, zielony, niebieski, biały, czarny i inne Szybkie wykrywanie uszkodzonych pikseli Intuicyjny interfejs – test ekranu w zaledwie kilka sekund Sprawdzenie kontrastu – porównaj zestawienie koloru tekstu z kolorem tła Pobierz RGB Test i upewnij się, że Twój ekran działa perfekcyjnie!

About

ChangeUnits2

This powerful utility app offers lightning-fast and accurate unit conversions for a wide range of needs. It includes advanced math functions, currency exchange, time zone tracking, and even chemical equation balancing. Designed for professionals and everyday users alike, it works offline and remembers your last calculations.

Highlights
  • Extreme speed and accuracy
  • Offline functionality
  • Currency exchange converter
  • Global time zone tracking
  • Advanced math functions
  • Chemical equation balancing
  • Last 33 calculations remembered
Features
Read full description

Designed by an Engineer from the Semiconductor Industry, ChangeUnits2 is Built for Extreme Speed and Versatility. ChangeUnits2 is Very Fast. ChangeUnits2 is Very Accurate. ChangeUnits2 Fits inside your Pocket and Doesn't Require a Signal. ChangeUnits2 even Knows what Time it will be HERE (in your Current Location) at 7am in Tokyo. ChangeUnits2 is Built for EVERYONE. It has a Button for virtually ANY Unit and is Very Easy to Use. Tap on the Woman Welder on the Right to Launch the Quick Unit Selection Screen. Toggle the "Longform List" / "Engineering List" button to Switch Between 1) a List of Unit Buttons in Shortform Engineering style, or 2) in Longform style for a more Wordy Description. note: this ALSO toggles between Scientific Notation & Standard Decimal Form. Quickly change between Thermal Units of BTUs / Therms / Kwh / kCals / and even Gallons of Gasoline Need even more Significant Figures? Just add Zero's to the end of the number you entered, press "Convert Units" and ChangeUnits2 will do the rest. Use the built in Currency Converter travelCash, travelCash2, travelCash3 and travelCash4 to Easily VISUALIZE ANY Monetary Exchange Rate. Whether the Exchange Rate is in [Dollars : Donuts] or [Donuts : Dollars]....ChangeUnits2 handles it like a Pro! Effortlessly Calculate the Number of Pints of Beer held in a 1/2 Barrel Keg for your Big Football Party. Converting Between Standard and Metric has never been so Easy!! Easily keep track of the Time in Major Cities while you are ANYWHERE in the World!! No signal needed. Use the Globe Buttons to arrange International Meetings.....based on your Preferred Time....or even Theirs. Schedule a meeting at 7am Tokyo time, or 7am Los Angeles time. ConvertUnits2 will help you keep track of time like a Pro. Perform advanced math functions right in the App. It's so easy and convenient! Even exponents, Ln, Log, Prime Numbers and Square Roots. Balance Chemical Equations from ANYWHERE! Now you can bring your Periodic Table of the Elements with You! Thank you, Uncle Sam! Calculate the Minimum Fall Time / Maximum Energies / Maximum Speeds of a Fall from nearly ANY Height. Now you're the real life McGuber! The "Last Values" button Remembers your Last 33 Calculations using "Convert Units" Now you can show Data you compiled right on your iPhone without re-entering the Information. It's so Easy ChangeUnits2 will Change your Life for the Better It's a Science & Engineering Professional's Dream!

Screenshots

RGB Test3 screens
ChangeUnits24 screens

Verdict

The call

The clearest difference is price: RGB Test at Free against ChangeUnits2's $0.99. ChangeUnits2's advantage is ads (none vs shown) and update cadence (every 4 weeks vs every 8 months). On in-app purchases 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

RGB Test is free to download; ChangeUnits2 costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

RGB Test ships an update every 8 months, ChangeUnits2 every 4 weeks. The most recent releases landed on September 16, 2026 and June 1, 2026 respectively.

Scorecard4 real differences · 5 level
RGB Test versus ChangeUnits2: the parameters behind the verdict, then further details
ParameterRGB TestChangeUnits2
PriceFree — better$0.99
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 8 monthsEvery 4 weeks — better
AdsYesNo — better
In-app purchasesNoNo
Monetization—Paid
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS26.015.6 — better
Further details — not scored
Size5 MB17 MB
Age rating9+4+
DeveloperZbigniew OsadaJack McCormack

In-app purchases

None

RGB Test

No in-app purchases

None

ChangeUnits2

No in-app purchases

Questions

Is RGB Test free?
RGB Test is free to download, with no in-app purchases.
Is ChangeUnits2 free?
ChangeUnits2 costs $0.99, with no in-app purchases.
Do RGB Test or ChangeUnits2 have ads?
RGB Test shows ads; ChangeUnits2 does not.
Which is updated more often, RGB Test or ChangeUnits2?
RGB Test ships an update every 8 months, and ChangeUnits2 every 4 weeks. Most recently, RGB Test was updated on September 16, 2026 and ChangeUnits2 on June 1, 2026.

Other comparisons