# VocalClock vs Sigmakey

The clearest difference is rating: VocalClock at 4.8 against Sigmakey's 2.0. VocalClock also leads on in-app purchases (none vs 1) and ratings volume (4 vs 1). On price, ads and device support there is nothing between them.

Both are free to download. Sigmakey sells 1 one-off in-app purchase. VocalClock asks for nothing beyond the download.

VocalClock holds the better App Store score, 4.8 against 2.0. Both are backed by a comparable volume of ratings — 4 and 1 respectively.

## The numbers

| Metric | VocalClock | Sigmakey |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (4 ratings)](https://appshunter.io/ios/app/vocalclock-voice-timer-alarm/id6758654309/reviews)** | [2.0 (1 ratings)](https://appshunter.io/ios/app/sigmakey-math-keyboard/id6788025133/reviews) |
| Number of ratings | **4** | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 10 days | — |
| Monetization | **Free** | Free with in-app purchases |
| Size | 5 MB | 13 MB |
| Requires iOS | **18.6** | 26.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Khuyen Duong](https://appshunter.io/developer/1857157292) | [Andrii Bashta](https://appshunter.io/developer/1547467775) |

## What reviewers say

### VocalClock

[App page](https://appshunter.io/ios/app/vocalclock-voice-timer-alarm/id6758654309)

This app announces the time aloud at custom intervals, even when your screen is locked. It helps you stay focused by providing passive time awareness without interrupting your current task or app.

**Highlights:** Announces time at custom intervals, Runs in the background with screen locked, Adjustable announcement frequency, Customizable phrases before time announcement, Smart scheduling for specific days/times, Natural-sounding Siri voices

**Features:** macOS Compatibility

**In-app purchases:** none


### Sigmakey

[App page](https://appshunter.io/ios/app/sigmakey-math-keyboard/id6788025133)

This utility provides a specialized keyboard for typing mathematical expressions, including fractions, roots, and Greek letters, directly within any app. It supports LaTeX, Unicode, and image output, with on-device processing for privacy and speed.

**Highlights:** Full math keyboard layout, Two-dimensional cursor for exponents/numerators, Type LaTeX, Unicode, or rendered image, On-device typesetting, no network required, Symbol search, recent, and favorite symbols

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sigmakey Pro | $9.99 | one-time |


## Frequently asked questions

### Is VocalClock free?

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

### Is Sigmakey free?

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

### Which has better reviews, VocalClock or Sigmakey?

VocalClock is rated higher. VocalClock averages 4.8 out of 5 from 4 ratings, while Sigmakey averages 2.0 from 1 ratings.

### Do VocalClock or Sigmakey have ads?

Neither VocalClock nor Sigmakey shows ads.

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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.*