Comparison

Psychrometer °F vs CTRAPR

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

Head to head
About

Psychrometer °F

This app calculates thermal comfort by evaluating heat, cold, dryness, and moisture. It provides detailed air property calculations and indicates if conditions are within a comfortable range, with easy dial input and color-coded temperature.

Highlights
  • Thermal comfort calculation
  • Air property analysis
  • Color-coded temperature
  • Dial input
  • Outdoor weather integration
  • Psychrometer type selection
Features
Read full description

Psychrometer °F is a psychrometric calculator for evaluating thermal comfort and moist-air conditions using U.S. customary units. Adjust temperature and humidity easily with the on-screen dials. Temperatures are color-coded for quick reference, and a “Good” indicator appears when conditions are between 68–82°F and 30–60% relative humidity. Choose from the following input combinations: • Dry-bulb temperature and relative humidity • Dry-bulb temperature and dew-point or frost-point temperature • Dry-bulb temperature and wet-bulb temperature The app displays or calculates: • Dry-Bulb Temperature (°F) • Wet-Bulb Temperature (°F) • Dew Point / Frost Point (°F) • Relative Humidity (%RH) • Humidity Ratio / Mixing Ratio (gr/lb) • Absolute Humidity (gr/ft³) • Enthalpy (Btu/lb) • Specific Volume (ft³/lb) • Atmospheric Pressure (inHg) • Vapor Pressure (inHg) • Saturation Vapor Pressure (inHg) Comfort Indices: • Heat Index based on the U.S. National Weather Service method • Simplified indoor WBGT based on dry- and wet-bulb temperatures • Discomfort Index (DI) The app also displays risk levels and easy-to-understand indicators for each selected index. Atmospheric Pressure: Choose from standard atmospheric pressure, the device’s built-in barometer on supported devices, or manual entry. Selecting the barometer may require Motion & Fitness access because iOS manages pressure-sensor permission through this setting. Outdoor Conditions: Tap the Outdoor Air button to retrieve the current temperature, relative humidity, and weather conditions for your location from Apple Weather. Location access is requested only when this feature is used. This feature retrieves weather information; it does not directly measure the air conditions around your device. Psychrometer Types: • Assmann — Aspirated psychrometer with forced ventilation; provides the highest measurement accuracy. • Wall-Mounted — August psychrometer using natural airflow; simple and convenient, but less accurate. • Sling — Swung by hand to move air across the thermometers; portable and suitable for outdoor use. Assmann is the default setting. Tapping Reset or Outdoor Air returns the app to Assmann mode. Wall-Mounted and Sling modes use wet-bulb input. Psychrometric Process Reference: You can also explore psychrometric processes without using a psychrometric chart. • In dew-point input mode (°F DP), keep the dew point fixed and adjust the upper dial to observe heating and cooling changes. • In wet-bulb input mode (°F WB), keep the wet-bulb temperature fixed and adjust the upper dial to observe humidification and dehumidification changes. • To examine steam humidification, use relative-humidity input mode (%) and adjust the lower dial. Calculation Methods: The Sonntag equations are used for saturation vapor pressure. Vapor-pressure calculations use the Sprung, August, or Ferrel psychrometric relationships according to the selected psychrometer type. Relative humidity is calculated according to WMO conventions. The input range is intentionally wide, but extreme combinations may increase numerical error or fall outside the practical range of the formulas. Rounding and internal unit conversions may also cause the least significant digits to change when switching input modes. Results are provided for reference only. Although care is taken to ensure accuracy, results are not guaranteed. The developer is not responsible for any damage, loss, or disadvantage resulting from use of this app. This app contains ads. A one-time in-app purchase removes the banner ad and the full-screen ad shown at launch.

About

CTRAPR

Easily manage your profile, register for events, and access important information. Purchase tickets, keep your details current, and stay updated with the latest news. This app provides a streamlined experience for event management and connectivity.

Highlights
  • Profile management
  • Event registration
  • Ticket purchasing
  • Information access
  • Notifications
  • User data updates
Features
Read full description

Con nuestra app, gestionar tu perfil, registrarte en eventos y acceder a información relevante nunca ha sido tan fácil. Compra tus boletos, mantén tu información actualizada y recibe notificaciones sobre las últimas novedades. Optimizada para ofrecerte una experiencia ágil y eficiente, esta aplicación es tu puerta de entrada a los eventos y recursos. ¡Simplifica tu gestión y mantente siempre conectado!

Screenshots

Psychrometer °F4 screens
CTRAPR3 screens

Verdict

The call

The clearest difference is in-app purchases: CTRAPR at none against Psychrometer °F's 1. CTRAPR also leads on ads (none vs shown) and rating (5.0 vs 4.5). Psychrometer °F's advantage is ratings volume (133 vs 2). On price, 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. Psychrometer °F sells 1 one-off in-app purchase. CTRAPR asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

CTRAPR holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: Psychrometer °F has 133 ratings behind it against 2, so its average is the more settled of the two.

UpkeepUpdate frequency

Psychrometer °F ships an update every 5 months, CTRAPR every 6 months. The most recent releases landed on November 1, 2026 and November 4, 2026 respectively.

Scorecard6 real differences · 4 level
Psychrometer °F versus CTRAPR: the parameters behind the verdict, then further details
ParameterPsychrometer °FCTRAPR
PriceFreeFree
Rating4.5 (133 ratings)5.0 (2 ratings) — better
Positive reviews66.7% of reviews—
Number of ratings133 — better2
Update frequencyEvery 5 months — betterEvery 6 months
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationAd-supportedFree — better
DevicesiPhoneiPhone, iPod — better
Requires iOS18.615.1 — better
Further details — not scored
Size9 MB34 MB
Age rating4+17+
DeveloperJUN KANAYAMACentrix Corporation

Customer experience

Psychrometer °F

All ratings133 ratings
Positive89.5%
Neutral4.5%
Negative6.0%
Written reviews6 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

CTRAPR

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

1 purchases

Psychrometer °F

One-time1
  • Remove Ads$3.99
None

CTRAPR

No in-app purchases

Questions

Is Psychrometer °F free?
Psychrometer °F is free to download, with in-app purchases available.
Is CTRAPR free?
CTRAPR is free to download, with no in-app purchases.
Which has better reviews, Psychrometer °F or CTRAPR?
CTRAPR is rated higher. Psychrometer °F averages 4.5 out of 5 from 133 ratings, while CTRAPR averages 5.0 from 2 ratings.
Do Psychrometer °F or CTRAPR have ads?
Psychrometer °F shows ads; CTRAPR does not.
Which is updated more often, Psychrometer °F or CTRAPR?
Psychrometer °F ships an update every 5 months, and CTRAPR every 6 months. Most recently, Psychrometer °F was updated on November 1, 2026 and CTRAPR on November 4, 2026.

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