# RedCrab Calculator vs Ecall

The clearest difference is in-app purchases: Ecall at none against RedCrab Calculator's 1. Ecall also leads on ads (none vs shown). RedCrab Calculator's advantage is update cadence (fortnightly vs every 6 weeks) and iOS requirement (15.6 vs 17.0). On price and device support there is nothing between them.

Both are free to download. RedCrab Calculator sells 1 one-off in-app purchase. Ecall asks for nothing beyond the download.

RedCrab Calculator ships an update fortnightly, Ecall every 6 weeks. The most recent releases landed on November 1, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | RedCrab Calculator | Ecall |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Fortnightly** | Every 6 weeks |
| Monetization | Free with in-app purchases | — |
| Size | 5 MB | 23 MB |
| Requires iOS | **15.6** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [少泽 梁](https://appshunter.io/developer/897112791) | [DREAMCORE CREATIONS PTE. LTD](https://appshunter.io/developer/1883779000) |

## What reviewers say

### RedCrab Calculator

[App page](https://appshunter.io/ios/app/redcrab-calculator/id947845140)

This powerful scientific calculator offers a modern UI and robust engine for users of all levels. It handles basic arithmetic to complex engineering equations with smart expression parsing and a high-precision display. Enjoy a seamless calculation experience with features like history recall and dark mode.

**Highlights:** Basic & Advanced Calculations, Smart Expression Parsing, Calculation History & Reuse, High-Precision Display, Dark Mode & Modern UI, VIP Ad-Free Experience

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 终身会员 | $1.99 | one-time |


### Ecall

[App page](https://appshunter.io/ios/app/ecall-guard-shield/id6760695403)

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

**In-app purchases:** none


## Frequently asked questions

### Is RedCrab Calculator free?

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

### Is Ecall free?

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

### Do RedCrab Calculator or Ecall have ads?

RedCrab Calculator shows ads; Ecall does not.

### Which is updated more often, RedCrab Calculator or Ecall?

RedCrab Calculator ships an update fortnightly, and Ecall every 6 weeks. Most recently, RedCrab Calculator was updated on November 1, 2026 and Ecall on November 5, 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.*