# CATS Input Method Pro vs eCalculator

The clearest difference is in-app purchases: CATS Input Method Pro at none against eCalculator's 1. CATS Input Method Pro also leads on ads (none vs shown). eCalculator's advantage is update cadence (every 3 months vs every 24 months) and iOS requirement (11.0 vs 17.0). On price and device support there is nothing between them.

Both are free to download. eCalculator sells 1 one-off in-app purchase. CATS Input Method Pro asks for nothing beyond the download.

CATS Input Method Pro ships an update every 24 months, eCalculator every 3 months. The most recent releases landed on August 26, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | CATS Input Method Pro | eCalculator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (151 ratings)](https://appshunter.io/ios/app/ecalculator-enhanced-edition/id1592915998/reviews)** |
| Number of ratings | — | **151** |
| Positive reviews | — | 80.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 24 months | **Every 3 months** |
| Monetization | — | Free with in-app purchases |
| Size | 7 MB | 77 MB |
| Requires iOS | 17.0 | **11.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [YIU LEUNG RANDY CHAN](https://appshunter.io/developer/1474191447) | [Ratha Sou](https://appshunter.io/developer/590343618) |

## What reviewers say

### CATS Input Method Pro

[App page](https://appshunter.io/ios/app/cats-input-method-pro/id1523143711)

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

**In-app purchases:** none


### eCalculator

[App page](https://appshunter.io/ios/app/ecalculator-enhanced-edition/id1592915998)

This app enhances the standard calculator with advanced features like history, equation viewing, and a scientific mode. It offers specialized calculators for fractions, programming, and tips, along with extensive unit and currency conversions. Personalize your experience with themes and keyboard input.

**Highlights:** Basic and scientific calculations, Fraction calculator, Programmer calculator (binary, octal, decimal, hex), Unit and currency converter, Tip calculator and bill splitter, Calculation history and equation view, Widget support and keyboard input

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Version | $4.99 | one-time |


## Frequently asked questions

### Is CATS Input Method Pro free?

CATS Input Method Pro is free to download, with no in-app purchases.

### Is eCalculator free?

eCalculator is free to download, with in-app purchases available.

### Do CATS Input Method Pro or eCalculator have ads?

eCalculator shows ads; CATS Input Method Pro does not.

### Which is updated more often, CATS Input Method Pro or eCalculator?

CATS Input Method Pro ships an update every 24 months, and eCalculator every 3 months. Most recently, CATS Input Method Pro was updated on August 26, 2026 and eCalculator on September 28, 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.*