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 has been designed to help heating engineers and surveyors gather information about a property for the installation of a heating system. The options available for heat loss reports are renewable technologies such as Air Source Heat Pumps, Ground Source Heat Pumps, Biomass or conventional fossil fuels. Please visit our website to create an account and watch our training videos. www.heat-engineer.com Heat Engineer Software Ltd is an Industrial Associate Supporter of the Chartered Institute of Plumbing & Heating Engineering. ----Heat Engineer has three functions ---- 1 - Heat Loss survey, designed to meet BS EN 12831, CIBSE Domestic Heating Design Guide and MCS standards. When the survey is completed you can send it to your account at www.heat-engineer.com 2 - MCS 020 Planning Standards, sound assessment for Air Source Heat Pumps. 3 - A quick heat loss estimator tool. -----Important useful feature---- Every entry made is automatically saved in the app’s history so you can revisit any time to amend either your sound assessment or heat loss survey. For MCS 020 Sound assessments this is particularly useful if you don’t know the sound power decibel rating whilst on site and haven’t yet decided which manufacturer to use. You can use the app on site to record data you have and revisit your history to update the project once you’re back in the office. We now have a LiDAR feature. 1----Heat Loss Survey---- Complete a site survey for a room by room heat loss calculation. The parameters within this app are detailed so calculations can be carried out following the domestic heating design guide and requirements to meet MCS standards. This tool is for collecting details of a property so you can then send it to an online Heat Engineer account. If you are a Heat Engineer account holder at www.heat-engineer.com then you can review your survey and produce a detailed heat loss report. Take photos for each room and installation locations. • Pre-populated drop down lists for room names and options to add custom names. • Pre-populated drop down lists and options to add custom description and U values for all building materials, walls, floors, windows, doors, ceilings and roof. • For ‘complex rooms’, rooms with lofted/vaulted ceilings and roof an option to select which image profile, so measurement and wall types can quickly be entered. • Current Emitter selection, quickly select the radiator profile image from our list and enter the height and length. Heat Engineer online www.heat-engineer.com will calculate the output based on the designed flow temperature in the final report. • Send completed survey to a Heat Engineer account online at www.Heat-Engineer.com • Surveys submitted for the heat loss calculation the ‘internal room design temperatures’ and ‘air changes per hour ‘will be based on the room name and age of the room. Energy kWh demand and running costs is calculated using degree day data. Fuel comparisons are also available. 2----MCS 020 Planning Standards, sound assessment for Air Source Heat Pumps- To ensure a proposed Air Source Heat Pump installation is a ‘permitted development’ for sound conditions use this app if you’re an MCS installer for the handover pack. • Enter any manufacturer and model name • Enter the A weighted sound power (dB) level for the chosen model (you can change this information in the history when you decide which model you want to install) • Enter a description of assessment position • Take and add a photo of the assessment position for your final PDF report • A clear indication of assessment results • Send a two page PDF report of the completed MCS 020 assessment to your office via email 3----Heat Loss Estimator---- This heat loss estimator tool has been designed to provide heating estimations on Power kW and Energy kWh demands for domestic and commercial properties. The tool provides approximations to aid the quotation / tendering process before a project is accepted.

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 (15.6 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 August 5, 2026 and September 20, 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 (167 ratings) — better
Positive reviews78.9% of reviews — better16.3% of reviews
Number of ratings—167 — better
Update frequencyEvery 2 monthsEvery 2 months
AdsNoNo
In-app purchasesYesYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better18.0
Further details — not scored
Size44 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 August 5, 2026 and testo Smart on September 20, 2026.

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