Comparison

VocalClock vs Sigmakey

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

VocalClock

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
Read full description

Stop checking your phone just to see the time. VocalClock announces the time aloud at any interval you choose, and keeps working even when your screen is locked. Stay focused, stay present, and let time come to you. STAY IN FLOW Lock your phone. Play music. Switch apps. VocalClock runs in the background and speaks the time without interrupting what you're doing. No more breaking concentration just to glance at the clock. ANY INTERVAL YOU NEED Set announcements from seconds to hours: • Every 30 seconds for precision timing • Every 5 minutes during workouts • Every hour while working • Any custom interval that fits your routine SPEAK IT YOUR WAY • Add a custom phrase before the time • Hear just the time if you prefer • Enable seconds for exact precision • Choose from natural-sounding Siri voices SMART SCHEDULING You don’t need announcements all day. VocalClock speaks only when you want it to: • Choose specific days of the week • Set active start and end times • Delay the start for future sessions DESIGNED FOR • Workouts and interval training • Cooking and task timing • Deep work and productivity • Meditation and mindfulness • Presentations and speaking practice • Anyone who wants passive awareness of time Simple. Reliable. Built to just work. Questions? Email us at: vocalclock.app@gmail.com

About

Sigmakey

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
Read full description

Sigmakey is a math keyboard for people who need to type actual math, anywhere you can type at all. Fractions, exponents, roots, Greek letters, and matrices sit one tap away, and the cursor moves right into a numerator or an exponent, so scientific notation looks the way it should. - A full math keyboard layout that works in any app with a text field - A two-dimensional field with a cursor that steps into fractions and powers - Type LaTeX, plain Unicode, or a rendered image, whichever the app expects - Everything typeset on device, with no network - Search for a symbol, or grab a recent or a favorite Drop an equation into a note, a message, or a homework app without hunting through menus. Privacy Policy: https://docs.google.com/document/d/e/2PACX-1vTDX9pxPOlUJl_skVUHPi99mAw0y2B2BYd_v1mJkoF3xW3rlOcW5KlYd4t93MMbbGhctSTnBTy7d_l6/pub Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

VocalClock4 screens
Sigmakey4 screens

Verdict

The call

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.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

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

ReceptionRating · Positive reviews · Number of ratings

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.

Scorecard5 real differences · 5 level
VocalClock versus Sigmakey: the parameters behind the verdict, then further details
ParameterVocalClockSigmakey
PriceFreeFree
Rating4.8 (4 ratings) — better2.0 (1 ratings)
Positive reviews100.0% of reviews—
Number of ratings4 — better1
Update frequencyEvery 10 days—
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.6 — better26.0
Further details — not scored
Size5 MB13 MB
Age rating4+4+
DeveloperKhuyen DuongAndrii Bashta

Customer experience

VocalClock

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Sigmakey

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%

In-app purchases

None

VocalClock

No in-app purchases

1 purchases

Sigmakey

One-time1
  • Sigmakey Pro$9.99

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.

Other comparisons