Comparison

iRelativity vs SpaceFold

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

Head to head
About

iRelativity

Features
Read full description

Every time you move, time passes slightly slower for you than for someone standing still. That's not science fiction โ€” it's special relativity, and it's happening to you right now. iRelativity uses your real GPS speed to calculate exactly how much time dilation you're experiencing. Every trip, every commute, every flight adds a tiny slice of time to your lifetime total. The faster you travel, the more you save. Features โ€ข Live time dilation โ€” your phone's GPS feeds real velocity into the Lorentz equation in real time โ€ข Lifetime total โ€” watch your accumulated time saved grow across every journey, displayed in the most readable unit from femtoseconds up to seconds โ€ข Daily history โ€” a chart of how much time you've saved each day โ€ข Global leaderboard โ€” compare your lifetime total with other travellers via Game Center โ€ข What-if simulator โ€” drag a slider toward the speed of light and see what time dilation would feel like at 0.9 c โ€ข Learn tab โ€” interactive animations of the light clock and Einstein's train thought experiment, with a Lorentz factor calculator The numbers are real. At highway speeds you save about a nanosecond per hour. Board a plane and that climbs to microseconds. The physics is identical to the corrections that keep GPS satellites accurate every day.

About

SpaceFold

Features
Read full description

SpaceFold is an interactive AR learning experience that transforms the Theory of Relativity into something you can see, explore, and understand. Instead of relying on complex equations, SpaceFold uses Augmented Reality, interactive simulations, and intelligent explanations to help users build an intuitive understanding of space, time, and motion. FEATURES โ€ข Spacetime Fabric Place a spacetime grid in your environment and watch it bend under the influence of mass. Explore gravity as the curvature of spacetime and discover how objects naturally move through curved geometry. โ€ข Time Walk Become a moving observer and experience the effects of time dilation. Compare clocks, explore motion near light speed, and understand how time changes depending on your journey. โ€ข Observer Perspective Switch between different reference frames and see how events can appear differently to different observers. Learn why simultaneity is relative and why there is no universal clock. โ€ข Intelligent Explanations Powered by Apple Foundation Models, SpaceFold provides contextual explanations based on your interactions, helping transform observations into understanding. WHY SpaceFold? Physics is often taught through equations and diagrams. SpaceFold takes a different approach by allowing users to interact directly with the concepts behind relativity through immersive AR experiences. Whether you're a student or simply curious about the universe, SpaceFold offers a visual and intuitive way to explore one of the most fascinating ideas in modern physics. Experience physics. See space. Fold time.

Screenshots

iRelativity4 screens
SpaceFold4 screens

Verdict

The call

The clearest difference is iOS requirement: iRelativity at 18.6 against SpaceFold's 26.0. On price, ads, in-app purchases and device support there is nothing between them.

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

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Scorecard1 real difference ยท 5 level
iRelativity versus SpaceFold: the parameters behind the verdict, then further details
ParameteriRelativitySpaceFold
PriceFreeFree
Update frequencyโ€”Weekly
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.6 โ€” better26.0
Further details โ€” not scored
Size1 MB6 MB
Age rating4+4+
DeveloperVladimir Kostadinov StoyanovGALGOTIAS UNIVERSITY,SCHOOL OF BUSINESS

In-app purchases

None

iRelativity

No in-app purchases

None

SpaceFold

No in-app purchases

Questions

Is iRelativity free?
iRelativity is free to download, with no in-app purchases.
Is SpaceFold free?
SpaceFold is free to download, with no in-app purchases.
Do iRelativity or SpaceFold have ads?
Neither iRelativity nor SpaceFold shows ads.

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