Uncertainty Calculator vs Gurfa Tahfeez
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Uncertainty Calculator
This app allows users to perform error propagation calculations for mathematical expressions involving uncertain variables. It supports absolute and relative error inputs, various functions, and trigonometric calculations in degrees or radians. The tool helps ensure accurate reporting of results based on estimated errors.
- Error propagation calculations
- Absolute and relative error input
- Support for mathematical functions
- Trigonometric calculations (degrees/radians)
- Variable combination in expressions
- Significant figure guidance
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Uncertainty Calculator evaluates the error propagation throughout the mathematical expressions comprised of variables of uncertain value. The application allows input of up to three value-error pairs (A, B and C), that can be used as a parameters in the final expression. Error values should be provided in absolute (100 +/- 5) or in relative format, the latter should appear in percent format (100 +/- 5%). The evaluated expression can include numerous functions, that provided by row of the appropriate buttons. Components and functions can be added directly to the expression field by pressing the corresponding buttons. To encompass expression into the preset formula, select the expression and press the corresponding formula button. Particular attention should be paid to placing brackets to avoid equation ambiguity. The application deals with independent, random errors. So if this is a case never use A + A, but rather 2*A and never A*A*A but rather A^3! Obviously, different parameters can be combined in any way (A+B or C *A^2 .. is perfectly fine). Angles for trigonometric functions can be provided in degrees or radians, and that should be reflected by setting a yellow button to "DEG" or "RAD". Bear in mind the importance of units in any of calculations! Implementation Examples: 1.The charge passing through an electrical circuit is defined by: Q = I * t, where I is the current and t is the time. Calculate the total charge value when a current of 0.15 ± 0.01 A passes through the circuit for 120 ± 1 s: Input: A = 0.15 ± 0.01, B = 120 ± 1 The final expression will be A*B, and press Calculate: The final value will be: 18 ± 1.2 Thus, it can be reported the total charge as 18 C ± 1 C. Important! One should only report as many significant figures as are consistent with estimated error! So the value should be rounded to the rightmost decimal place at which error applies. 2. A ball is tossed straight up into the air with initial speed vo = (4.0± 0.2) m/s. After a time t = (0.60 ± 10%) s, the height of the ball is h = vo*t - 0.5gt^2 = 0.636 m (g = 9.80 m/s^2). What is the value and uncertainty of height? Input: A = vo = 4.0 ± 0.2, and B = t = 0.60 ± 10%, then the final expression should be: A*B – 0.5*9.8*B^2 The final value will be: 0.6 ± 0.4 (meters).
Gurfa Tahfeez
This video call application facilitates online Quran classes and assessments for Mahad al-Zahra. It offers easy login for educators and learners, organized class lists, and a chat feature for communication. Enjoy high-quality audio and video for uninterrupted learning.
- Easy login for teachers and students
- Class-time sorted lists
- In-app chat for communication
- High-quality video and audio calls
- Disturbance-free learning environment
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Gurfa Tahfeez is a video call application designed specially for Mahad al-Zahra's online Quran classes and ikhtebaar. Some of its prominent features are: 1) Easy login option for teachers and students. 2) Class-time wise sorted students' and teachers' list. 3) Chat option to communicate with the teacher before and after the class. 4) High quality video and audio call for smooth and hassle free class sessions. Learn Quran without disturbances.
Screenshots
Verdict
The clearest difference is price: Gurfa Tahfeez at Free against Uncertainty Calculator's $3.99. Gurfa Tahfeez also leads on ratings volume (6 vs 1) and iOS requirement (15.1 vs 17.0). Uncertainty Calculator's advantage is rating (5.0 vs 2.2). On update cadence, 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
Gurfa Tahfeez is free to download; Uncertainty Calculator costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Uncertainty Calculator holds the better App Store score, 5.0 against 2.2. That said, the two scores are not equally well evidenced: Gurfa Tahfeez has 6 ratings behind it against 1, so its average is the more settled of the two.
Uncertainty Calculator ships an update every 3 months, Gurfa Tahfeez every 2 months. The most recent releases landed on September 14, 2026 and August 23, 2026 respectively.
| Parameter | Uncertainty Calculator | Gurfa Tahfeez |
|---|---|---|
| Price | $3.99 | Free — better |
| Rating | 5.0 (1 ratings) — better | 2.2 (6 ratings) |
| Positive reviews | — | 0.0% of reviews |
| Number of ratings | 1 | 6 — better |
| Update frequency | Every 3 months | Every 2 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.0 | 15.1 — better |
| Further details — not scored | ||
| Size | 1 MB | 35 MB |
| Age rating | 4+ | 4+ |
| Developer | Roman Volinsky | Mahad al Zahra |
Customer experience
Uncertainty Calculator
Gurfa Tahfeez
In-app purchases
Uncertainty Calculator
No in-app purchases
Gurfa Tahfeez
No in-app purchases
Questions
Is Uncertainty Calculator free?
Is Gurfa Tahfeez free?
Which has better reviews, Uncertainty Calculator or Gurfa Tahfeez?
Do Uncertainty Calculator or Gurfa Tahfeez have ads?
Which is updated more often, Uncertainty Calculator or Gurfa Tahfeez?
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