Comparison

Radioactivity vs RelativityTheory

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

Head to head
About

Radioactivity

Features
Read full description

Radioactivity K12 Learning app helps us to know about Radioactive Decay, Nuclear Fission and Fusion. Our app makes it easy for kids and students to understand the uses and safety measures of Radioactivity. Our objective is to make this science concept simple to understand for students and get in-depth knowledge of the subject. There are three sections in the app: Each section is targeted to develop the student’s skills. Radioactivity app is designed to provide extra help for each and every physics student. Radiation & Radioactivity: This section explains the complete definition of Radiation, Radioactivity and Radioisotopes. *Radioactive Decay - There are three types of Radioactive Decay - namely Alpha Decay, Beta Decay and Gamma Decay based on the respective radiations Alpha, Beta and Gamma radiations. *Nuclear Fission - A large nucleus splits to form two smaller nuclei and some neutrons.This section explains two kinds of Nuclear Fission namely spontaneous fission and Neutron-induced fission. *Nuclear Fusion - Two small nuclei come together and join to form a large nucleus, releasing energy. 2) Uses & Safe Handling: This section explains about Uses & Safe Handling of Radioactive elements. Radioactivity is used for various functionalities in industries and medicine like Smoke detector, Thickness measurement, Leak detection. 3) Quiz: An interactive quiz to check the knowledge with score board. Download the Radioactivity app and other K12 educational apps published by Ajax Media Tech and make your kids shine in science.

About

RelativityTheory

Features
Read full description

Introducing and explaining the mysterious phenomenon derived from the theory of relativity. In particular, we will detail the changes in the way time progresses. The interstellar flight screen shows how time progresses in response to rocket speed. Shows the difference in how time progresses between rockets and the earth in space travel. The GPS screen shows that gravity changes the way time progresses.

Screenshots

RelativityTheory2 screens

Verdict

The call

The clearest difference is update cadence: RelativityTheory at every 3 weeks against Radioactivity's every 36 months. RelativityTheory also leads on device support (3 vs 1). Radioactivity's advantage is iOS requirement (12.0 vs 14.4). On price, ads and in-app purchases there is nothing between them.

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Radioactivity costs $0.99 and RelativityTheory $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Radioactivity ships an update every 36 months, RelativityTheory every 3 weeks. The most recent releases landed on September 16, 2026 and September 13, 2026 respectively.

Scorecard3 real differences Β· 3 level
Radioactivity versus RelativityTheory: the parameters behind the verdict, then further details
ParameterRadioactivityRelativityTheory
Price$0.99$0.99
Update frequencyEvery 36 monthsEvery 3 weeks β€” better
AdsNoNo
In-app purchasesNoNo
DevicesiPadiPhone, iPad, iPod β€” better
Requires iOS12.0 β€” better14.4
Further details β€” not scored
Size52 MB6 MB
Age rating4+4+
Developerwww.ajaxmediatech.comTakao Akatsu

In-app purchases

None

Radioactivity

No in-app purchases

None

RelativityTheory

No in-app purchases

Questions

Is Radioactivity free?
Radioactivity costs $0.99, with no in-app purchases.
Is RelativityTheory free?
RelativityTheory costs $0.99, with no in-app purchases.
Do Radioactivity or RelativityTheory have ads?
Neither Radioactivity nor RelativityTheory shows ads.
Which is updated more often, Radioactivity or RelativityTheory?
Radioactivity ships an update every 36 months, and RelativityTheory every 3 weeks. Most recently, Radioactivity was updated on September 16, 2026 and RelativityTheory on September 13, 2026.

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