# Halcyon Calc Lite vs ThetaCalc

The clearest difference is in-app purchases: ThetaCalc at none against Halcyon Calc Lite's 3. ThetaCalc also leads on ads (none vs shown) and review sentiment (100% vs 67%). Halcyon Calc Lite's advantage is rating (4.6 vs 4.3) and ratings volume (15 vs 4). On price, update cadence, device support and iOS requirement there is nothing between them.

Both are free to download. Halcyon Calc Lite sells 3 one-off in-app purchases. ThetaCalc asks for nothing beyond the download.

Halcyon Calc Lite holds the better App Store score, 4.6 against 4.3. Both are backed by a comparable volume of ratings — 15 and 4 respectively. Written reviews complicate that: 67% of Halcyon Calc Lite's written reviews are positive against 100% of ThetaCalc's, so the app with the better star average is not the one people write more warmly about.

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on October 31, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | Halcyon Calc Lite | ThetaCalc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (15 ratings)](https://appshunter.io/ios/app/halcyon-calc-lite/id408004888/reviews)** | [4.3 (4 ratings)](https://appshunter.io/ios/app/thetacalc/id1521614636/reviews) |
| Number of ratings | **15** | 4 |
| Positive reviews | 66.7% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 3 months | Every 3 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 13 MB | 1 MB |
| Requires iOS | **16.6** | 17.6 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Halcyon Touch Software](https://appshunter.io/developer/327064662) | [Felix Stehli](https://appshunter.io/developer/1521614638) |

## What reviewers say

### Halcyon Calc Lite

[App page](https://appshunter.io/ios/app/halcyon-calc-lite/id408004888)

This app is a powerful calculator for students and professionals, offering advanced features like symbolic expression manipulation, graphing, and statistical analysis. It supports real, complex, and integer numbers, matrices, and vectors, making it versatile for various mathematical tasks.

**Highlights:** Symbolic expression manipulation, Graphing of expressions, Matrix and vector calculations, Statistical analysis, Multiple number formats (decimal, hex, octal, binary), Over 225 built-in operations

**Features:** Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Directory And Unit Conversion Support | $0.99 | one-time |
| Programming Support | $1.99 | one-time |
| Larger Display Upgrade | $1.99 | one-time |


### 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 Halcyon Calc Lite free?

Halcyon Calc Lite is free to download, with in-app purchases available.

### Is ThetaCalc free?

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

### Which has better reviews, Halcyon Calc Lite or ThetaCalc?

Halcyon Calc Lite is rated higher. Halcyon Calc Lite averages 4.6 out of 5 from 15 ratings, while ThetaCalc averages 4.3 from 4 ratings.

### Do Halcyon Calc Lite or ThetaCalc have ads?

Halcyon Calc Lite shows ads; ThetaCalc does not.

### Which is updated more often, Halcyon Calc Lite or ThetaCalc?

Halcyon Calc Lite ships an update every 3 months, and ThetaCalc every 3 months. Most recently, Halcyon Calc Lite was updated on October 31, 2026 and ThetaCalc on October 29, 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.*