Comparison

Heat Engineer vs testo Smart

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

Head to head
About

Heat Engineer

This app assists heating engineers and surveyors in collecting property data for heating system installations. It supports heat loss reports for various technologies and includes tools for sound assessments and quick estimations. Data is automatically saved for later review and amendment.

Highlights
  • Heat loss survey for BS EN 12831, CIBSE, and MCS standards
  • MCS 020 sound assessment for Air Source Heat Pumps
  • Quick heat loss estimator tool
  • Automatic data saving and history for amendments
  • Room-by-room heat loss calculation
  • Photo capture for rooms and installation locations
  • Fuel comparisons and running cost calculations
Features
Read full description

Heat Engineer Software helps heating engineers and surveyors capture property information on site, carry out heat loss surveys and assess air source heat pump sound levels. From a quick estimate to a detailed room-by-room survey (3D LiDAR scanning), gather the information you need for heat pump and conventional heating system design. Work from your iPhone or iPad, then continue with your project in the Heat Engineer desktop platform. ROOM-BY-ROOM HEAT LOSS SURVEYS Capture the property details needed for heat loss calculations designed to follow BS EN 12831-1:2017, the CIBSE Domestic Heating Design Guide and relevant MCS requirements. • Create rooms using preset or custom names. • Record room dimensions, building materials and construction details. • Select materials from the built-in library or enter custom descriptions and U-values. • Record walls, floors, windows, doors, ceilings and roofs. • Capture complex room shapes and vaulted ceilings using illustrated profiles. • Record existing radiator types and dimensions to support emitter assessment. • Add photographs of rooms and proposed installation locations. • Continue your survey in the desktop platform to review calculations and produce detailed reports. CHOOSE HOW YOU MEASURE Use a tape measure or laser measure and enter your measurements, or use built-in LiDAR scanning on a compatible iPhone or iPad to capture room dimensions and layouts. Choose the survey method that suits the property and the equipment you have available. LiDAR scanning requires a compatible device with a LiDAR sensor. FLOOR PLANS AND LIDAR SCANNING Bring your survey to life with a visual layout of the property. • Scan rooms using supported LiDAR devices. • View captured rooms and layouts. • See room dimensions and radiator locations within your floor plans. • Export 2D floor plans to PDF for use alongside your project documentation. WHOLE-HOUSE HEAT LOSS AND QUICK ESTIMATES Assess a property before progressing to a detailed room-by-room survey. Use whole-house heat loss and quick estimation tools to support early discussions, initial project assessments and quotation preparation. Preliminary estimates help you get started. Complete a detailed room-by-room calculation to support final heating system and emitter design. AIR SOURCE HEAT PUMP SOUND ASSESSMENTS Carry out sound assessments to support assessment of the noise requirements associated with permitted development. • Record the proposed heat pump manufacturer and model. • Enter the manufacturer’s A-weighted sound power level. • Record the assessment position and add supporting photographs. • Review the assessment result. • Return to an assessment to update equipment details or site information. • Produce a PDF assessment report for your project records. A sound assessment addresses noise criteria; other planning requirements may also apply. CONNECTED FROM SITE TO DESKTOP Keep your mobile survey and desktop project connected with the updated Heat Engineer platform. Save your work, revisit surveys and assessments, and continue adding information as the project develops. Capture details on site, then use the desktop platform for further design work and reporting. GET STARTED A Heat Engineer account is required. Visit our website to create an account, explore the platform and watch our training videos

About

testo Smart

This app supports measurements for refrigeration, HVAC, and heating systems. It also aids in food safety, frying oil quality, and indoor climate monitoring. Quickly interpret data, create digital reports with photos, and send them via email.

Highlights
  • All-in-one system measurements
  • Graphical display of measured values
  • Digital PDF/CSV measurement reports
  • Email report sharing
  • Leak test analysis
  • Automatic refrigerant charging
  • Indoor air quality monitoring
Features
Read full description

- All in one: The testo Smart App supports you with measurements on refrigeration, air conditioning, and heating systems, as well as in ensuring the safety and quality of food and frying oil, and in monitoring indoor climate and storage conditions. - Fast: Graphically descriptive display of measured values, e.g. as a table, for quick interpretation of results. - Efficient: Create digital measurement reports including. photos as PDF/ CSV files on site and send them via e-mail. The testo Smart App is compatible with the following Bluetooth®-enabled measuring instruments from Testo: - Thermal imager testo 860i for smartphones - All Testo Smart Probes - Digital manifolds testo 550s/557s/558s/550i/570s and testo 550/557 - Digital refrigerant scale testo 560i - Vacuum pump testo 565i - Flue gas analyzer testo 300/310 II/310 II EN - Vacuum gauge testo 552 - Clamp meter testo 770-3 - Volume flow hood testo 420 - Compact HVAC measuring instruments - Frying oil tester testo 270 BT - Temperature meter testo 110 Food - Dual purpose IR and penetration thermometer testo 104-IR BT - Data loggers 174 T BT & 174 H BT - Online data loggers testo 160, testo 162 & testo 164 GW Applications with the testo Smart App Refrigeration systems, air conditioning systems and heat pumps, heating systems, indoor air quality: - Leak test: Recording and analysis of the pressure drop curve. - Superheat and subcooling: Automatic determination of condensation and evaporation temperature and calculation of superheat / subcooling. - Target superheat: Automatic calculation of target superheat - Automatic refrigerant charging by weight, by superheat, by subcooling, and by target superheat - Vacuum measurement: Graphical progress display of the measurement with indication of start and differential value Indoor climate monitoring: - Indoor air quality: automatic calculation of the dew point and wet-bulb temperature - Temperature, humidity, lux, UV, pressure, CO2: the right data logger for every application – from a single solution to an online monitoring system" Ventilation systems: - Volume flow: After the intuitive input of the duct cross-section, the app calculates the volume flow fully automatically. - Diffuser measurements: simple parameterisation of the diffuser (dimensions and geometry), comparison of the volume flows of several diffusers when setting up a ventilation system, continuous and multi-point average calculation. Heating systems: - Flue gas measurement: Second screen function in combination with testo 300 - Measurement of gas flow and static gas pressure: Also possible parallel to the flue gas measurement (delta P) - Measurement of flow and return temperatures (delta T) Thermography: - Determining Delta T on heating, refrigeration/air conditioning, and industrial systems - Detecting hot/cold spots - Assessing the risk of mold Food safety: Temperature Control Points (CP/CCP): - Seamless documentation of measured values to fulfill HACCP specifications - Individually definable limit values and measurement comments within the App for each measurement point - Reporting and data export for regulatory requirements and internal quality assurance Frying oil quality: - Seamless documentation of measured values as well as calibration and adjustment of the measurement instrument - Individually definable limit values and measurement comments within the App for each measurement point - Reporting and data export for regulatory requirements and internal quality assurance --------------------------------------------------------- Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://www.testo.com/en/company/privacy-policy-app

Screenshots

Heat Engineer4 screens
testo Smart4 screens

Verdict

The call

The clearest difference is review sentiment: Heat Engineer at 79% against testo Smart's 16%. Heat Engineer also leads on monetization model (free vs free with in-app purchases) and iOS requirement (16.4 vs 18.0). On price, update cadence, ads and in-app purchases 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. Heat Engineer sells 1 one-off in-app purchase and testo Smart sells 5 in-app purchases, starting at $6.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

Scorecard3 real differences · 7 level
Heat Engineer versus testo Smart: the parameters behind the verdict, then further details
ParameterHeat Engineertesto Smart
PriceFreeFree
Rating—2.7 (170 ratings) — better
Positive reviews78.9% of reviews — better16.3% of reviews
Number of ratings—170 — better
Update frequencyEvery 2 monthsEvery 2 months
AdsNoNo
In-app purchasesYesYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.4 — better18.0
Further details — not scored
Size306 MB195 MB
Age rating4+4+
DeveloperHeat Engineer Software LtdTesto SE & Co. KGaA

Customer experience

Heat Engineer

Written reviews19 reviews
Positive78.9%
Neutral0.0%
Negative21.1%

testo Smart

All ratings167 ratings
Positive35.9%
Neutral13.2%
Negative50.9%
Written reviews153 reviews
Positive16.3%
Neutral17.6%
Negative66.0%

Bugs and requests

Heat Engineer

Not enough reviews yet to summarise bugs or requests.

testo Smart

Reported bugs

5 issues
  • App won't connect to devices
  • Compatibility issues with newer iOS versions
  • Frequent crashes and freezes
  • Inability to save favorite refrigerants
  • Measurement data not displaying properly

Requested features

7 requests
  • Add option to toggle Bluetooth discovery
  • Improve Bluetooth range
  • Add ability to customize colors and graphs
  • Improve data export functionality
  • Add option to name sensors
Show 2 more
  • Improve multi-probe support
  • Integrate more features from physical devices

In-app purchases

1 purchases

Heat Engineer

One-time1
  • MCS 020 PDF Report Token$2.99
5 purchases

testo Smart

Subscriptions4
  • Multi-site measurement7 Days trial$6.991 Month
  • Air balancing7 Days trial$9.991 Month
  • Multi-site measurement$69.901 Year
Show 1 more
  • Air balancing$99.901 Year
One-time1
  • Logging digital manifold$44.99

Questions

Is Heat Engineer free?
Heat Engineer is free to download, with in-app purchases available.
Is testo Smart free?
testo Smart is free to download, with in-app purchases available.
Do Heat Engineer or testo Smart have ads?
Neither Heat Engineer nor testo Smart shows ads.
Which is updated more often, Heat Engineer or testo Smart?
Heat Engineer ships an update every 2 months, and testo Smart every 2 months. Most recently, Heat Engineer was updated on November 1, 2026 and testo Smart on November 3, 2026.

Other comparisons