InterCalc vs Great Circle Tool
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
InterCalc
This app performs linear interpolation using a set of X-Y values to define a relationship. It can calculate values based on defined points, useful for tasks like converting pressure readings to fluid volumes in containers or performing simple unit conversions.
- Linear interpolation of X-Y values
- Defines arbitrary functions from data points
- Calculates fluid volume from pressure readings
- Performs unit conversions (e.g., temperature, speed)
- Supports custom data sets
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This application is designed to linearly interpolate a value given a set of X-Y values that define a relationship. The X-Y values can be as simple as two points that specify a simple line, or they can be a set of points that specifies an arbitrary function. One use of this program is to calculate the amount of fluid in a container given a pressure reading at the bottom of the tank. Typically this situation results in several pressure readings and corresponding volume ( gallons, liters ) readings as the tank is being filled. Once the pressure measuring device is so calibrated, pressure readings can then be converted to gallon or liter values. Other uses include simple conversions between Fahrenheit and Celsius, or between kph and mph.
Great Circle Tool
Calculate the shortest distance between two points on Earth's surface. Ideal for pilots, it estimates flight times based on aircraft speed. A valuable planning utility for aviation professionals.
- Great circle distance calculation
- Airport to airport distance
- Flight time estimation
- Aircraft speed input
- Pilot planning tool
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This is an app to quickly measure the great circle distance between two points or airports around the globe. It is a great tool for pilots who can add the aircraft speed and get an estimate of the flight time as well. A must have planning tool for all pilots!
Screenshots
Verdict
The clearest difference is price: InterCalc at Free against Great Circle Tool's $2.99. InterCalc also leads on rating (5.0 vs 2.6). Great Circle Tool's advantage is update cadence (every 4 days vs every 11 months) and ratings volume (5 vs 1). 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
InterCalc is free to download; Great Circle Tool costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.
InterCalc holds the better App Store score, 5.0 against 2.6. That said, the two scores are not equally well evidenced: Great Circle Tool has 5 ratings behind it against 1, so its average is the more settled of the two.
InterCalc ships an update every 11 months, Great Circle Tool every 4 days. The most recent releases landed on October 1, 2026 and October 7, 2026 respectively.
| Parameter | InterCalc | Great Circle Tool |
|---|---|---|
| Price | Free — better | $2.99 |
| Rating | 5.0 (1 ratings) — better | 2.6 (5 ratings) |
| Positive reviews | — | 33.3% of reviews |
| Number of ratings | 1 | 5 — better |
| Update frequency | Every 11 months | Every 4 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free — better | Paid |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 18.6 | 9.3 — better |
| Further details — not scored | ||
| Size | 1 MB | 11 MB |
| Age rating | 4+ | 4+ |
| Developer | River Rock Logic | Learrocket Productions, LLC |
Customer experience
InterCalc
Great Circle Tool
In-app purchases
InterCalc
No in-app purchases
Great Circle Tool
No in-app purchases
Questions
Is InterCalc free?
Is Great Circle Tool free?
Which has better reviews, InterCalc or Great Circle Tool?
Do InterCalc or Great Circle Tool have ads?
Which is updated more often, InterCalc or Great Circle Tool?
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