Comparison

Thermometer vs iCelsius

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

Head to head
About

Thermometer

This app transforms your iPhone or iPod Touch into a thermometer, displaying the exact outside temperature based on your current location. It provides detailed local weather conditions and allows you to check temperatures for other cities.

Highlights
  • Real-time outdoor temperature display
  • Location-based temperature readings
  • Local weather condition reports
  • Temperature checks for other cities
  • Celsius and Fahrenheit support
  • Universal app for all devices
Features
Read full description

Thermometer is the number 1 thermometer application on the AppStore. The most accurate thermometer application on the AppStore! Thermometer is the original and top selling application that turns your iPhone or iPod Touch into a thermometer. This application will tell you the exact outside temperature based on your current location (GPS or WiFi). An animation will show you the current outdoor temperature on an stylish red LED thermometer. ************************************************************ FEATURES : ************************************************************ ◉ Universal app. This application works on your iPad, iPhone or iPod Touch. One version for all devices! ◉ Local temperature based on your current position (GPS or WiFi). ◉ Local condition report, temperature, high & low, wind speed & direction, and humidity level. ◉ You can check the temperature for other cities. Choose the city you want to see weather for by scrolling through your saved cities. You can add or delete cities, and reorder your list. PLEASE, ENTER THE CITY AND THE COUNTRY. ◉ The temperature is displayed in Celsius or Fahrenheit. ◉ The most accurate thermometer application on the AppStore. ◉ The application is available in English, French, Spanish, Italian, German and Japanese. IMPORTANT : This application requires an active Internet connection to retrieve data. You also need to turn on "Location Services" option in the settings of your iPhone. If you like this application, please leave us a review on iTunes. Your support would greatly help. Thank you for taking the time to report any bugs or to request an enhancement to Thermometer application. Feedback is very important to us. We will do our best to answer queries. Email us at support@presselite.com

About

iCelsius

Transform your iPhone, iPad, or iPod touch into a digital thermometer with this app. It works with a separate hardware probe to measure temperatures of liquids and other substances, create graphs, and set alerts. Ideal for cooking, science education, and quality control.

Highlights
  • Live temperature display
  • Temperature graphing with pan/zoom
  • Configurable temperature alarms
  • Snapshot and continuous recording
  • Recipe presets for cooking
  • History of recorded readings
Features
Read full description

Extend your Smartphone, Sense the World. The iCelsius is a temperature probe that turns the iPhone, iPad or iPod touch into a digital thermometer. IMPORTANT - Requires separate hardware available from http://www.icelsius.com to operate. The app can work in demo mode if no probe is connected. Compatible with wired and wireless (Wi-Fi) iCelsius probes! The current app downloaded from the App store will read temperature, create graphs and set up alerts. Please visit our website www.icelsius.com for more information! A stainless steel tip makes it possible to measure liquid temperatures such as baby formula, cooking ingredients, wine, tea, household appliances and hundreds of other applications. Can also be used in school or for teaching science, for equipment calibration, food quality control, cold chain control. The application is constantly improved based on user feedback. FEATURES • Live Display – shows useful temperature data in one shot • Graphs – with pan and zoom touch support • Alarms – Generate alarms when temperature goes outside a configurable (lower and/or upper) limit. • Snapshot Record – Ability to record a single reading, along with title, picture and note. • Continuous Record – Ability to continuously record readings as well as to add notes, take a picture and drop a pin on the graph. • History – Access all your previous records. • Recipes – For cooking and barbecue, choose preset recipe or create your own. Find more probes & wireless measurement devices on our product website www.icelsius.com and company website website www.aginova.com.

Screenshots

Thermometer3 screens
iCelsius2 screens

Verdict

The call

The clearest difference is in-app purchases: iCelsius at none against Thermometer's 1. iCelsius also leads on ads (none vs shown). Thermometer's advantage is ratings volume (4.2K vs 139) and rating (4.4 vs 4.2). On price, review sentiment, update cadence 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. Thermometer sells 1 one-off in-app purchase. iCelsius asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Thermometer holds the better App Store score, 4.4 against 4.2. That said, the two scores are not equally well evidenced: Thermometer has 4.2K ratings behind it against 139, so its average is the more settled of the two. Written reviews complicate that: 30% of Thermometer's written reviews are positive against 35% of iCelsius's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on September 27, 2026 and August 18, 2026 respectively.

Scorecard5 real differences · 5 level
Thermometer versus iCelsius: the parameters behind the verdict, then further details
ParameterThermometeriCelsius
PriceFreeFree
Rating4.4 (4.2K ratings) — better4.2 (139 ratings)
Positive reviews30.1% of reviews35.2% of reviews — better
Number of ratings4.2K — better139
Update frequencyEvery 2 monthsEvery 2 months
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.012.0 — better
Further details — not scored
Size48 MB41 MB
Age rating4+4+
DeveloperAlexandre MorcosAginova Sarl

Customer experience

Thermometer

All ratings4,229 ratings
Positive84.6%
Neutral4.9%
Negative10.5%
Written reviews332 reviews
Positive30.1%
Neutral6.9%
Negative63.0%

iCelsius

All ratings139 ratings
Positive81.3%
Neutral5.0%
Negative13.7%
Written reviews54 reviews
Positive35.2%
Neutral13.0%
Negative51.9%

User reviews

Thermometer

From 4.2K App Store ratings

What we love

  • 👍 Simple and easy to use
  • 🚀 Quick temperature display
  • 💡 Useful for checking outdoor temperature

Room to improve

  • 🐛 Inaccurate temperature readings
  • 🔍 Doesn't measure room/indoor temperature
  • 💤 Doesn't update temperature in real-time
  • 🔋 High battery consumption
  • 📢 Excessive ads even in paid version

iCelsius

From 139 App Store ratings

What we love

  • 👍 Accurate temperature readings
  • 👍 Handy for monitoring
  • 👍 Good for remote monitoring
  • 👍 Works well for specific uses (e.g., cigars, BBQ)
  • 👍 Good UI and graphing (when it works)

Room to improve

  • 🐛 Frequent crashes
  • 🐛 Connectivity issues (Wi-Fi, Bluetooth)
  • 🐛 Unreliable remote sensing
  • 🐛 Inconsistent readings/inaccurate
  • 🐛 Hardware failures (probes dying)

Bugs and requests

Thermometer

Reported bugs

3 issues
  • App crashes frequently
  • Doesn't detect location properly
  • Reported temperatures are inconsistent

Requested features

3 requests
  • Option to display indoor temperature
  • Real-time temperature updates
  • Ability to set temperature alerts/alarms

iCelsius

Reported bugs

33 issues
  • App crashes on startup
  • App crashes when tapping graphs
  • Temperature readings are incorrect/flashing
  • Live view display is messed up
  • App crashes when phone locks or switches apps
Show 28 more
  • Connectivity issues (Wi-Fi, Bluetooth)
  • Unit not recognized when connected directly
  • App crashes on iPhone X
  • App crashes on iPad and iPhone
  • App crashes repeatedly after latest update
  • Device becomes inoperable after update
  • Pop-up to download newer version persists
  • Probes show infinity or out of range readings
  • Wi-Fi connection drops when iPad goes to sleep
  • Dual probe app has only one set of alarm points
  • App freezes when looking for Wi-Fi
  • Unit not supported by iOS device error
  • Wire leading to probe not ovenproof
  • Recipe function only has high range for one probe
  • Degrees C vs F display issues
  • Graph display substandard
  • App doesn't update temperature when not running
  • App doesn't track temperature prior to current session after restart
  • Unit never connects to home wireless network
  • Temperature gauge no longer reports decimal values
  • Recent update makes app useless
  • Cannot tell if unit is charged
  • Sensor inaccurate out of the box
  • Sensor stopped working after a week or two
  • App shows wrong temperatures in demo mode
  • Graph zoom is useless (cannot zoom out to longer time scales)
  • Cannot zoom temp scale without zooming time scale
  • App doesn't run under iOS 7

Requested features

18 requests
  • Fix crashing issues
  • Improve Wi-Fi and Bluetooth connectivity
  • Ensure compatibility with newer iOS versions
  • Improve remote monitoring reliability
  • Fix data loss when switching apps
Show 13 more
  • Add dual alarm points for dual probes
  • Improve recipe function (high range for one probe)
  • Fix Celsius/Fahrenheit display issues
  • Improve graph display (zoom, time span, temp span)
  • Allow background notifications/alarms
  • Add ability to call/text on alarm
  • Make probes ovenproof
  • Improve probe durability/lifespan
  • Allow power supply via mini USB
  • Separate time and date columns in CSV export
  • Allow zooming on temperature scale in graphs
  • Make app work without hardware (demo mode improvement)
  • Improve documentation for non-techies

In-app purchases

1 purchases

Thermometer

One-time1
  • Temperature Forecast$1.99
None

iCelsius

No in-app purchases

Questions

Is Thermometer free?
Thermometer is free to download, with in-app purchases available.
Is iCelsius free?
iCelsius is free to download, with no in-app purchases.
Which has better reviews, Thermometer or iCelsius?
Thermometer is rated higher. Thermometer averages 4.4 out of 5 from 4.2K ratings, while iCelsius averages 4.2 from 139 ratings.
Do Thermometer or iCelsius have ads?
Thermometer shows ads; iCelsius does not.
Which is updated more often, Thermometer or iCelsius?
Thermometer ships an update every 2 months, and iCelsius every 2 months. Most recently, Thermometer was updated on September 27, 2026 and iCelsius on August 18, 2026.

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