Comparison

Spacetime Clock vs iCalculator

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

Head to head
About

Spacetime Clock

Explore celestial mechanics and terrestrial positioning with this app. Visualize moon phases, Earth's rotation, and your location's latitude and longitude. It also includes a compass and level meter for your device.

Highlights
  • Moon phases visualization
  • Earth rotation and revolution simulation
  • Latitude and longitude display
  • Compass functionality
  • iPhone level meter
  • Customizable background colors
Features
Read full description

Time, calendars, the movements and positions of celestial bodies, and direction are all closely connected. This app brings together time and place in one view. Alongside the time and date, it shows the phases of the Moon, Earth’s rotation and orbit, latitude and longitude, compass direction, and the iPhone’s level. It lets you see and feel where you are in time and space at a glance. [Top of Screen] MOON: Moon phase (lunar age 0–29) HOURS: Hours (24-hour cycle) MINUTES: Minutes (60-minute cycle) SECONDS: Seconds (60-second cycle) [Center of Screen] The year, month, date, hour, minute, day of the week, and second are displayed. Earth completes one circuit around the center of the screen in 365 days (366 in a leap year). The display uses Earth’s axial tilt to approximate the amount of daylight at that time of year. It does not show precise sunrise or sunset times. The Earth and Moon graphics change depending on whether your current latitude is in the Northern or Southern Hemisphere. [Bottom of Screen] LATITUDE: Latitude (−90° to +90°; positive values indicate north, negative values south) LONGITUDE: Longitude (−180° to +180°; positive values indicate east, negative values west) COMPASS: Direction of north LEVEL: Level, measured along the iPhone’s X and Y axes Choose from four background colors: Space, Midnight, Twilight, and Sky Blue.

About

iCalculator

This app offers a powerful and intuitive calculator experience, featuring both basic and scientific functions. It calculates results instantly as you type and allows for easy editing and history management. Customize your experience with themes and integrate it seamlessly as a keyboard or Today Widget.

Highlights
  • Instant calculation without '=' button
  • Basic & Scientific Calculator
  • Fraction & Expression Calculator
  • History List with iCloud sync
  • Customizable themes
  • Keyboard extension for any app
  • Today Widget support
Features
Read full description

Award-winning calculator app for iPad and iPhone with no ads. Designed with simplicity, usability, and beauty in mind! Join millions of users by downloading iCalculator on your iPhone, or iPad. [QUICK START] * There is no "=" button in this calculator app. It will calculate and show the result as soon as the expression is updated. If you need the next calculation, please click "CE" button; if you want to edit the calculation, please click "Del" button. * Swipe up/down to hide/show the history records. * Swipe left and right to hide/show the scientific/math functions. [How to add a keyboard calculator] 1. Go to Settings > General > Keyboard. 2. Tap Keyboards, then do any of the following: Add a keyboard: Tap Add New Keyboard, then choose "iCalculator" from the list. 3. When the screen changes, touch "iCalculator" and "Allow full access". [How to add the Today Widget] 1. In Today View, scroll to the bottom. You should find an Edit button. Tap it. 2. A new Add Widgets screen appears with a list of widgets. There are two lists here. The first lists the active widgets in your Today View. Scroll down until you see the More Widgets section, which is the widgets not in your Today View. 3. Find the widget "iCalculator". Tap the “+” icon. The widget will move to the bottom of the list of active widgets above the More Widgets section. [FEATURES] • No push, no news, no ads, 6.5MB, booting under one second. * Basic & Scientific Calculator * Fraction & Expression Calculator * Calculate and show results instantly when the input is updated. * History List: all Calculations are Saved and can be Copied and Forwarded; hide and open with one simple click * Quick Equation Preview: Your current Equation is displayed below the result * Basic Calculation Buttons in Portrait view * Advanced Mathematical/Scientific Buttons in Landscape view * Equations are automatically saved to the History list, which syncs with iCloud. * Use the fraction key to do coherent fractional math. Calculate fractions: add, subtract, divide and multiply. * Full support for iPad Split Screen multi-tasking. * Install the iCaculator keyboard so you can calculate a question in any app. Tap the "Insert" button, and the answer is inserted in the text field. * Made a mistake? Tap the current equation to enter edit mode, where you can select characters, insert and delete. * Apply 16 beautiful themes, including new entrants Candy, Mint, Lava, and a “bright themes” set. * Use the Theme Creator to make your own bright and beautiful color scheme. Purchase service: ##Services support the developer by keep working on it and adding new features. If you do not subscribe to the service, it does not affect any features. ##The service is valid for one month and will be automatically renewed upon expiration ##Account will be charged for renewal within 24-hours before the end of the current period, and identify the cost of the renewal ##Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings after purchase Privacy Policy and Terms: http://www.ledego.com/apps/icalculator/privacy.html

Screenshots

Spacetime Clock4 screens
iCalculator4 screens

Verdict

The call

The clearest difference is price: Spacetime Clock at Free against iCalculator's $1.99. Spacetime Clock also leads on in-app purchases (none vs 1). iCalculator's advantage is rating (5.0 vs 2.8) and review sentiment (76% vs 41%). On ratings volume and ads 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

Spacetime Clock is free to download; iCalculator costs $1.99 up front. iCalculator sells 1 in-app purchase, starting at $0.49 per month. Spacetime Clock asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

iCalculator holds the better App Store score, 5.0 against 2.8. Both are backed by a comparable volume of ratings — 4 and 3 respectively. Written reviews point the same way: 41% of Spacetime Clock's written reviews are positive against 76% of iCalculator's.

UpkeepUpdate frequency

Spacetime Clock ships an update every 5 weeks, iCalculator every 9 days. Both last shipped on October 24, 2026.

Scorecard8 real differences · 2 level
Spacetime Clock versus iCalculator: the parameters behind the verdict, then further details
ParameterSpacetime ClockiCalculator
PriceFree — better$1.99
Rating2.8 (4 ratings)5.0 (3 ratings) — better
Positive reviews40.9% of reviews76.2% of reviews — better
Number of ratings4 — better3
Update frequencyEvery 5 weeksEvery 9 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhoneiPhone, iPad, iPod — better
Requires iOS16.013.0 — better
Further details — not scored
Size6 MB6 MB
Age rating4+4+
Developery-designNan Chao

Customer experience

Spacetime Clock

All ratings4 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews22 reviews
Positive40.9%
Neutral22.7%
Negative36.4%

iCalculator

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews42 reviews
Positive76.2%
Neutral7.1%
Negative16.7%

In-app purchases

None

Spacetime Clock

No in-app purchases

1 purchases

iCalculator

Subscriptions1
  • Monthly Subscription$0.491 Month

Questions

Is Spacetime Clock free?
Spacetime Clock is free to download, with no in-app purchases.
Is iCalculator free?
iCalculator costs $1.99, and also offers in-app purchases.
Which has better reviews, Spacetime Clock or iCalculator?
iCalculator is rated higher. Spacetime Clock averages 2.8 out of 5 from 4 ratings, while iCalculator averages 5.0 from 3 ratings.
Do Spacetime Clock or iCalculator have ads?
Neither Spacetime Clock nor iCalculator shows ads.
Which is updated more often, Spacetime Clock or iCalculator?
Spacetime Clock ships an update every 5 weeks, and iCalculator every 9 days. Most recently, Spacetime Clock was updated on October 24, 2026 and iCalculator on October 24, 2026.

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