# FunctionCalc vs ThetaCalc

The clearest difference is price: ThetaCalc at Free against FunctionCalc's $0.99. ThetaCalc also leads on iOS requirement (17.6 vs 26.2). FunctionCalc's advantage is rating (5.0 vs 4.3) and update cadence (every 8 days vs every 3 months). On review sentiment, ads, in-app purchases and device support there is nothing between them.

ThetaCalc is free to download; FunctionCalc costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

FunctionCalc holds the better App Store score, 5.0 against 4.3. Both are backed by a comparable volume of ratings — 13 and 4 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

FunctionCalc ships an update every 8 days, ThetaCalc every 3 months. The most recent releases landed on June 5, 2026 and June 1, 2026 respectively.

## The numbers

| Metric | FunctionCalc | ThetaCalc |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[5.0 (13 ratings)](https://appshunter.io/ios/app/functioncalc/id1455028714/reviews)** | [4.3 (4 ratings)](https://appshunter.io/ios/app/thetacalc/id1521614636/reviews) |
| Number of ratings | **13** | 4 |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 8 days** | Every 3 months |
| Monetization | Paid | **Free** |
| Size | 2 MB | 1 MB |
| Requires iOS | 26.2 | **17.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Lawler Innovations, Inc.](https://appshunter.io/developer/1455028713) | [Felix Stehli](https://appshunter.io/developer/1521614638) |

## What reviewers say

### FunctionCalc

[App page](https://appshunter.io/ios/app/functioncalc/id1455028714)

This all-in-one utility app helps veterans calculate VA disability benefits, track important dates, and perform everyday calculations. It includes a tip splitter, unit converter, and a powerful calculator with saved formulas.

**Highlights:** VA disability benefit calculator, Date countdown and elapsed time tracker, Tip calculator and bill splitting, Unit and currency converter, Time math and custom formulas, Full calculation history

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### ThetaCalc

[App page](https://appshunter.io/ios/app/thetacalc/id1521614636)

This utility app provides a Reverse Polish Notation (RPN) calculator. Users can extend its functionality by programming custom functions and equations using JavaScript.

**Highlights:** Reverse Polish Notation (RPN) calculator, User-programmable functions, JavaScript equation support, Extensible functionality

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is FunctionCalc free?

FunctionCalc costs $0.99, with no in-app purchases.

### Is ThetaCalc free?

ThetaCalc is free to download, with no in-app purchases.

### Which has better reviews, FunctionCalc or ThetaCalc?

FunctionCalc is rated higher. FunctionCalc averages 5.0 out of 5 from 13 ratings, while ThetaCalc averages 4.3 from 4 ratings.

### Do FunctionCalc or ThetaCalc have ads?

Neither FunctionCalc nor ThetaCalc shows ads.

### Which is updated more often, FunctionCalc or ThetaCalc?

FunctionCalc ships an update every 8 days, and ThetaCalc every 3 months. Most recently, FunctionCalc was updated on June 5, 2026 and ThetaCalc on June 1, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*