Comparison

Spacetime Clock vs Prime Speed Controller

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

Prime Speed Controller

Features
Read full description

Prime Speed Controller is a Safari extension that adds A-B loop repeat, playback speed control, seek, and time-saved tracking exclusively to Prime Video on iPhone and iPad. Perfect for language learners and anyone who wants to get more out of Prime Video. ■ A-B Loop Repeat Tap A to mark a start point, tap B to mark an end point — the video loops that segment continuously. Replay any dialogue, scene, or lecture as many times as you need. ■ Playback Speed 15 presets from 0.5x to 5x, with 0.05x fine-tuning. Subtle steps like 1.1x and 1.2x let you boost speed while keeping audio clear. ■ Forward & Rewind Choose 5, 10, 15, or 30-second intervals. Jump back instantly to catch missed dialogue. ■ Time-Saved Tracker The panel shows how much real time you have saved by watching above 1.0x speed, accumulated across sessions. Key Features • A-B Loop: mark any segment for continuous repeat • 15 playback speed presets from 0.5x to 5x • Fine-tune in 0.05x steps • Forward and rewind at 5, 10, 15, or 30 seconds • Time-saved tracker displayed in the panel • Settings saved automatically across sessions • Works on iPhone and iPad • Activates only on Prime Video — no other sites • No data sent to external servers How to Use 1. Follow the in-app guide to enable the extension in Safari Settings. 2. Open Prime Video in Safari and start a video. 3. Use the floating panel to set speed, seek interval, or A-B loop points. Playback speed or seeking may be restricted by Prime Video for certain titles. This app does not detect or skip advertisements. This is an independent, unofficial Safari extension. It is not provided, endorsed, or approved by Amazon, Prime Video, or their affiliates. Amazon and Prime Video are trademarks or registered trademarks of their respective owners.

Screenshots

Spacetime Clock4 screens
Prime Speed Controller4 screens

Verdict

The call

The clearest difference is device support: Prime Speed Controller at 3 against Spacetime Clock's 1. On price, ads, in-app purchases and iOS requirement 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. Neither carries in-app purchases, so what you see is what you pay.

Scorecard1 real difference · 9 level
Spacetime Clock versus Prime Speed Controller: the parameters behind the verdict, then further details
ParameterSpacetime ClockPrime Speed Controller
PriceFreeFree
Rating2.8 (4 ratings) — better—
Positive reviews40.9% of reviews—
Number of ratings4 — better—
Update frequencyEvery 5 weeks—
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
DevicesiPhoneiPhone, iPad, iPod — better
Requires iOS16.015.0 — better
Further details — not scored
Size6 MB1 MB
Age rating4+4+
Developery-designKohei Ishikawa

In-app purchases

None

Spacetime Clock

No in-app purchases

None

Prime Speed Controller

No in-app purchases

Questions

Is Spacetime Clock free?
Spacetime Clock is free to download, with no in-app purchases.
Is Prime Speed Controller free?
Prime Speed Controller is free to download, with no in-app purchases.
Do Spacetime Clock or Prime Speed Controller have ads?
Neither Spacetime Clock nor Prime Speed Controller shows ads.

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