Date.Time Calculator vs Harmonic Wave Equation Calc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Date.Time Calculator
Calculate date and time differences, intervals, and perform unit conversions with a pure calculator interface. Useful for determining future or past dates, calculating total time for multiple events, and converting between various time units and POSIX time.
- Date and time point calculations
- Time interval calculations
- Unit conversion of time
- POSIX time interconversion
- Time zone mutual conversion
- Arithmetic operations with time
Read full descriptionHide full description
Date.Time Calculator lets you easily perform calculations involving dates, times, and time intervals, as well as convert between units of time — all with the familiar feel of a calculator. Date.Time Calculator supports the following operations: * Basic arithmetic with numbers (integers and decimals) * Arithmetic with numbers and Time Intervals * Operations between Time Intervals (addition, subtraction, and division) * Operations between Time Intervals and Time Points (addition and subtraction) * Operations between Time Points (calculating the difference) * Conversion between units of time * Conversion to and from POSIX Time * Conversion between time zones Date.Time Calculator is especially useful for questions such as: * What date is 100 days from today? * What date and time was it 32,768 seconds ago? * If one lap takes 1 minute 32.6 seconds, how long will 62 laps take? * What time will it be after those 62 laps? * How many days have passed since January 23 of this year? * How many days are 100,000 seconds? * What date and time does POSIX Time 1234567890 represent? * What is the current time in POSIX Time? And with a little creativity, Date.Time Calculator can be useful in many other situations as well.
Harmonic Wave Equation Calc
This physics and math calculator quickly determines wave properties like displacement, velocity, and amplitude. It provides instant calculations with copyable results and includes reference formulas. Optimized for everyday use, it supports high precision and various units.
- Instant wave calculations
- Copyable results
- Included reference formulas
- Supports 16 decimal places
- Multiple unit support
- Ad-free and private
Read full descriptionHide full description
Harmonic Wave Equation Calculator is a physics/math calculator used to find the displacement of a given point along the wave, the position of that point, the time point, wave velocity, wavelength, amplitude, or initial phase of the wave quickly and easily. Features: - Instant calculation. - Results are copyable to other apps. - Formulas are included as references. - Supports up to 16 decimal places. - Supports various units for each input. - Works seamlessly on both iPhone and iPad. - Lightweight, compact app optimized for everyday use. - Ad-free and built with privacy in mind. A harmonic of such a wave is a wave with a frequency that is a positive integer multiple of the frequency of the original wave, known as the fundamental frequency. The original wave is also called the 1st harmonic; the following harmonics are known as higher harmonics. Formula: y = A * sin[(2π / λ) * (x - vt) + Φ] where: y - displacement of a given point along the wave x - position of that point (its distance from the source) t - time point v - wave velocity λ - wavelength A - amplitude Φ - initial phase of the wave Thank you for your support, and feel free to visit nitrio.com for more apps for your iOS devices.
Screenshots
Verdict
The clearest difference is update cadence: Date.Time Calculator at every 5 months against Harmonic Wave Equation Calc's every 31 months. Date.Time Calculator also leads on price ($0.99 vs $2.99). Harmonic Wave Equation Calc's advantage is iOS requirement (13 vs 15.6). On ads, in-app purchases, monetization model 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
Date.Time Calculator costs $0.99 and Harmonic Wave Equation Calc $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Date.Time Calculator ships an update every 5 months, Harmonic Wave Equation Calc every 31 months. The most recent releases landed on October 13, 2026 and October 10, 2026 respectively.
| Parameter | Date.Time Calculator | Harmonic Wave Equation Calc |
|---|---|---|
| Price | $0.99 — better | $2.99 |
| Rating | — | 5.0 (1 ratings) — better |
| Positive reviews | 0.0% of reviews | — |
| Number of ratings | — | 1 — better |
| Update frequency | Every 5 months — better | Every 31 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Devices | iPhone, iPod | iPhone, iPad, iPod — better |
| Requires iOS | 15.6 | 13 — better |
| Further details — not scored | ||
| Size | 1 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | Noriaki HASHIBA | Nitrio |
Customer experience
Date.Time Calculator
Harmonic Wave Equation Calc
In-app purchases
Date.Time Calculator
No in-app purchases
Harmonic Wave Equation Calc
No in-app purchases
Questions
Is Date.Time Calculator free?
Is Harmonic Wave Equation Calc free?
Do Date.Time Calculator or Harmonic Wave Equation Calc have ads?
Which is updated more often, Date.Time Calculator or Harmonic Wave Equation Calc?
Other comparisons















