Comparison

ZeroClock零时钟 vs Delta Calc

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

Head to head
About

ZeroClock零时钟

Features
Read full description

Time deserves more than one look. ZeroClock is a collection of fullscreen clocks crafted for iPhone and iPad. Place it on your desk, nightstand, or living-room shelf and turn your screen into a quiet, beautiful expression of time. From translucent Liquid Glass and precise Swiss Dial to spatial Ripple, Living Orrery, warm Nixie Glow, and shape-shifting Flux, every clock has its own proportions, typography, motion, and color. Why you'll love ZeroClock: • 27 handcrafted fullscreen clocks • Multiple color collections for every theme • Layouts individually refined for iPhone and iPad • 12/24-hour time, date, and seconds controls • Keep Screen Awake for desk and bedside display • English and Simplified Chinese • No ads, no account, and no personal data collection Start with 6 free clocks. A single ZeroClock Pro purchase permanently unlocks the other 21 premium clocks and every color collection. No subscription. Make every glance at the time worth a second look.

About

Delta Calc

Quickly calculate percent changes, discounts, and financial gains without complex math. Solve for any of the three values in the percent change formula with an intuitive interface and fun animations.

Highlights
  • Calculate percent changes
  • Solve for any variable in the formula
  • Customizable decimal places
  • Haptic feedback
  • Fun animations
  • Adjustable keyboard buttons
Features
Read full description

A fast, easy, and fun-to-use percent change calculator. Now you can quickly calculate discounts, financial gains, and percent changes without having to use Excel, Google, or do the long math. Delta Calc can solve for any of the three values within the percent change formula. It solves for the a, b, or c value in the percent change formula ((b - a) / a) * 100 = c. Other features include: - Haptic feedback (can be disabled if desired) - Change the number of decimal places displayed in the result (from 0 to 10) - Fun animation when tapping the swap button (warning: could become addictive) - Delightful to tap number pad buttons - Enable and disable keyboard buttons Terms: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy: https://deltacalc.app/privacy Support: https://deltacalc.app/support

Screenshots

ZeroClock零时钟4 screens
Delta Calc3 screens

Verdict

The call

The clearest difference is price: ZeroClock零时钟 at Free against Delta Calc's $0.99. ZeroClock零时钟 also leads on iOS requirement (15.6 vs 17.6). Delta Calc's advantage is update cadence (every 3 days vs every 3 weeks). On ads, in-app purchases 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

ZeroClock零时钟 is free to download; Delta Calc costs $0.99 up front. ZeroClock零时钟 sells 1 one-off in-app purchase and Delta Calc sells 3 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

ZeroClock零时钟 ships an update every 3 weeks, Delta Calc every 3 days. The most recent releases landed on October 10, 2026 and October 17, 2026 respectively.

Scorecard3 real differences · 6 level
ZeroClock零时钟 versus Delta Calc: the parameters behind the verdict, then further details
ParameterZeroClock零时钟Delta Calc
PriceFree — better$0.99
Rating—5.0 (2 ratings) — better
Number of ratings—2 — better
Update frequencyEvery 3 weeksEvery 3 days — better
AdsNoNo
In-app purchasesYesYes
Monetization—Paid
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better17.6
Further details — not scored
Size27 MB2 MB
Age rating4+4+
Developer昌飞 佘Stephen Coffey

In-app purchases

1 purchases

ZeroClock零时钟

One-time1
  • Premium$1.99
3 purchases

Delta Calc

Subscriptions2
  • Delta Calc Monthly$0.991 Month
  • Delta Calc Yearly$4.991 Year
One-time1
  • Delta Calc Lifetime$9.99

Questions

Is ZeroClock零时钟 free?
ZeroClock零时钟 is free to download, with in-app purchases available.
Is Delta Calc free?
Delta Calc costs $0.99, and also offers in-app purchases.
Do ZeroClock零时钟 or Delta Calc have ads?
Neither ZeroClock零时钟 nor Delta Calc shows ads.
Which is updated more often, ZeroClock零时钟 or Delta Calc?
ZeroClock零时钟 ships an update every 3 weeks, and Delta Calc every 3 days. Most recently, ZeroClock零时钟 was updated on October 10, 2026 and Delta Calc on October 17, 2026.

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