Comparison

Simple Pendulum Calculator vs ZEFNET Charge

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

Head to head
About

Simple Pendulum Calculator

This physics calculator quickly computes pendulum period, frequency, maximum height, energy, and speed. It supports various units, offers instant calculations with copyable results, and includes formulas for reference. Designed for privacy and efficiency, it works seamlessly on iOS devices.

Highlights
  • Instant pendulum calculations
  • Copyable results
  • Included formulas
  • Supports various units
  • High precision (16 decimal places)
  • Ad-free and private
Features
Read full description

The Simple Pendulum Calculator is a physics/math calculator designed to find the pendulum period, frequency, maximum height, energy of the system, or speed at the bottom quickly and easily. Features: - Instant calculation. - Results are copyable to other apps. - Formulas are included as reference. - 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 pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position. When released, the restoring force acting on the pendulum's mass causes it to oscillate about the equilibrium position, swinging back and forth. The time for one complete cycle, a left swing and a right swing, is called the period. The period depends on the length of the pendulum and also to a slight degree on the amplitude, the width of the pendulum's swing. Simple Pendulum equation: T = 2π * √L/g Where: T : Period of the simple pendulum L : Length of the pendulum g : Acceleration due to gravity, the standard gravity of Earth is 9.80665m/s2 The velocity at the bottom of the swing is: v = √2g * L * (1-cos(a)) Where: v : The velocity at the bottom of the pendulum a : The angle from the vertical The Maximum height is: H = L - L * cos(a) The system energy is: E = m * v2 / 2 Where: E : System energy m : Mass of the object v : The velocity at the bottom of the pendulum Thanks for your support, and do visit nitrio.com for more apps for your iOS devices.

About

ZEFNET Charge

Find and use public electric vehicle charging stations. Monitor and control your home charging unit, with options to override utility program restrictions for emergency charging.

Highlights
  • Find public chargers
  • Start/stop charging sessions
  • Secure in-app payments
  • Monitor home charger usage
  • Control home charger
  • Override charging restrictions
Features
Read full description

Access ZEF Energy's public chargers and your ZEFNET-enabled charger at home. This app provides access to ZEF Energy's network of public chargers, allowing drivers to find a charger, start/stop a charging session and pay for their session costs in a secure and simple way. It also provides drivers with a ZEFNET-enabled charger a way to monitor and control its usage. If your charger is participating in a utility program which restricts charging at certain times, this app provides the ability to override some program restrictions in order to charge in an emergency.

Screenshots

Simple Pendulum Calculator4 screens
ZEFNET Charge4 screens

Verdict

The call

The clearest difference is price: ZEFNET Charge at Free against Simple Pendulum Calculator's $2.99. ZEFNET Charge also leads on update cadence (every 4 months vs every 31 months) and ratings volume (6 vs 1). Simple Pendulum Calculator's advantage is rating (5.0 vs 2.0). On ads, in-app purchases 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

ZEFNET Charge is free to download; Simple Pendulum Calculator costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Simple Pendulum Calculator holds the better App Store score, 5.0 against 2.0. That said, the two scores are not equally well evidenced: ZEFNET Charge has 6 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Simple Pendulum Calculator ships an update every 31 months, ZEFNET Charge every 4 months. The most recent releases landed on September 10, 2026 and September 29, 2026 respectively.

Scorecard6 real differences · 4 level
Simple Pendulum Calculator versus ZEFNET Charge: the parameters behind the verdict, then further details
ParameterSimple Pendulum CalculatorZEFNET Charge
Price$2.99Free — better
Rating5.0 (1 ratings) — better2.0 (6 ratings)
Positive reviews—10.4% of reviews
Number of ratings16 — better
Update frequencyEvery 31 monthsEvery 4 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS1311.0 — better
Further details — not scored
Size1 MB19 MB
Age rating4+4+
DeveloperNitrioZEF Energy Inc.

Customer experience

Simple Pendulum Calculator

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

ZEFNET Charge

All ratings6 ratings
Positive16.7%
Neutral0.0%
Negative83.3%
Written reviews48 reviews
Positive10.4%
Neutral10.4%
Negative79.2%

In-app purchases

None

Simple Pendulum Calculator

No in-app purchases

None

ZEFNET Charge

No in-app purchases

Questions

Is Simple Pendulum Calculator free?
Simple Pendulum Calculator costs $2.99, with no in-app purchases.
Is ZEFNET Charge free?
ZEFNET Charge is free to download, with no in-app purchases.
Which has better reviews, Simple Pendulum Calculator or ZEFNET Charge?
Simple Pendulum Calculator is rated higher. Simple Pendulum Calculator averages 5.0 out of 5 from 1 ratings, while ZEFNET Charge averages 2.0 from 6 ratings.
Do Simple Pendulum Calculator or ZEFNET Charge have ads?
Neither Simple Pendulum Calculator nor ZEFNET Charge shows ads.
Which is updated more often, Simple Pendulum Calculator or ZEFNET Charge?
Simple Pendulum Calculator ships an update every 31 months, and ZEFNET Charge every 4 months. Most recently, Simple Pendulum Calculator was updated on September 10, 2026 and ZEFNET Charge on September 29, 2026.

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