Comparison

Psychrometry Chart vs PE Prep Pro

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

Head to head
About

Psychrometry Chart

This app calculates and displays thermodynamic properties of moist air mixtures. It supports both SI and imperial units, allowing users to find values like dry-bulb temperature, relative humidity, and enthalpy by interacting with a chart. It also computes thermal comfort parameters.

Highlights
  • Moist air property calculation
  • SI and imperial unit support
  • Interactive chart with reticle
  • Displays dry-bulb temp, humidity, enthalpy
  • Calculates PMV/PPD thermal comfort
Features
Read full description

The application is a psychrometric chart. It accurately calculates and displays relevant thermodynamic air & water vapour mixture properties. Supports both SI and imperial unit systems By sliding the reticle within the graph the properties values for each corresponding graph point are instantly updated and displayed in the respective fields. In particular the following properties are shown: Dry-bulb temperature, Relative humidity, Wet bulb temperature, Specific enthalpy & Dew point. Additionally ISO-7730 PMV/PPD thermal comfort parameters are calculated.

About

PE Prep Pro

This comprehensive exam preparation system offers over 1,400 realistic practice questions across 16 engineering disciplines. It provides detailed performance analytics to pinpoint weak areas and includes essential code summaries for offline study.

Highlights
  • 1,400+ realistic exam questions
  • 16 major engineering disciplines
  • Performance analytics
  • Offline functionality
  • Essential code summaries
Features
Read full description

This isn't just another study app - it's your complete PE exam success system designed by professional engineers. WHAT MAKES PE PREP PRO DIFFERENT: • 1,400+ REALISTIC exam questions across 16 major engineering disciplines • Questions based on codes & standards used in the real exam (ASCE 7, ACI 318, AISC, ASME BPVC, IEEE, NFPA, API, OSHA, EPA, and 25+ more) • Performance analytics to identify weak areas • 100% OFFLINE functionality - study anywhere, anytime COMPLETE DISCIPLINE COVERAGE: • Civil Engineering (Construction, Geotechnical, Structural, Transportation, Water Resources) • Mechanical Engineering (HVAC, Thermal/Fluids, Machine Design) • Electrical Engineering (Power Systems, Electronics & Controls, Computer Engineering) • Chemical Engineering • Structural Engineering • Nuclear Engineering • Petroleum Engineering • Environmental Engineering • Fire Protection Engineering • Control Systems Engineering • Mining & Mineral Processing • Metallurgical & Materials Engineering • Naval Architecture & Marine Engineering • Industrial & Systems Engineering • Architectural Engineering ESSENTIAL CODES & STANDARDS SUMMARIES INCLUDED: • ASCE 7 - Minimum Design Loads • ACI 318 - Structural Concrete Requirements • AISC Steel Construction Manual • International Building Code (IBC) • MUTCD - Traffic Control Devices • AASHTO Bridge Design Specifications • ASME BPVC - Boiler & Pressure Vessel Code • API Standards - Petroleum Industry • IEEE Standards - Electrical Systems • NFPA Codes - Fire Protection • OSHA (29 CFR) - Safety Regulations • EPA (40 CFR) - Environmental Compliance • NRC (10 CFR) - Nuclear Regulations • ASTM, ISO, SMACNA, NACE, ISA Standards PROVEN STUDY METHOD: Take diagnostic tests to identify knowledge gaps Study targeted practice questions with detailed explanations Reference essential code summaries and formulas instantly Track progress with detailed analytics Pass your PE exam with confidence START PASSING TODAY: Don't waste months with outdated study materials. PE Prep Pro gives you everything you need to pass your PE exam on the first try. Download now and start your path to Professional Engineer licensure. Download PE Prep Pro now and take the next step toward earning your P.E. license!

Screenshots

Psychrometry Chart3 screens
PE Prep Pro4 screens

Verdict

The call

The clearest difference is price: Psychrometry Chart at $1.99 against PE Prep Pro's $34.99. Psychrometry Chart also leads on update cadence (every 2 weeks vs every 4 weeks). On review sentiment, ads, in-app purchases and monetization model 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

Psychrometry Chart costs $1.99 and PE Prep Pro $34.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Psychrometry Chart ships an update every 2 weeks, PE Prep Pro every 4 weeks. The most recent releases landed on October 20, 2026 and October 19, 2026 respectively.

Scorecard2 real differences · 8 level
Psychrometry Chart versus PE Prep Pro: the parameters behind the verdict, then further details
ParameterPsychrometry ChartPE Prep Pro
Price$1.99 — better$34.99
Rating—2.0 (2 ratings) — better
Positive reviews0.0% of reviews0.0% of reviews
Number of ratings—2 — better
Update frequencyEvery 2 weeks — betterEvery 4 weeks
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.615.1 — better
Further details — not scored
Size3 MB31 MB
Age rating4++4
DeveloperKonstantinos LadiellisExamp, LLC

Customer experience

Psychrometry Chart

Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

PE Prep Pro

All ratings2 ratings
Positive0.0%
Neutral50.0%
Negative50.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

In-app purchases

None

Psychrometry Chart

No in-app purchases

None

PE Prep Pro

No in-app purchases

Questions

Is Psychrometry Chart free?
Psychrometry Chart costs $1.99, with no in-app purchases.
Is PE Prep Pro free?
PE Prep Pro costs $34.99, with no in-app purchases.
Do Psychrometry Chart or PE Prep Pro have ads?
Neither Psychrometry Chart nor PE Prep Pro shows ads.
Which is updated more often, Psychrometry Chart or PE Prep Pro?
Psychrometry Chart ships an update every 2 weeks, and PE Prep Pro every 4 weeks. Most recently, Psychrometry Chart was updated on October 20, 2026 and PE Prep Pro on October 19, 2026.

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