About
Created October 24, 2026
ReflexApp.online is a small guide site about reflex and reaction-time apps for Android. We started it for a simple reason: searching "Reflex app" gives you a pile of different apps with the same name, and most pages pretend they are all one app. They are not, and that mix-up wastes people's time.
What we do here
Our main focus is Reflex by Kranus Company, the brain-training app with the package name brain.reaction.concentration. We explain its reaction, memory and concentration games, how its millisecond scores work, and how to train with it in short daily sessions. Our guide to the Reflex app and its scores is the best place to start.
We also cover the namesakes honestly. Reflex!, ReflexTest by Daniel Hiebeler and RTap are separate reaction apps from separate developers, and ExploreLearning Reflex is a school math program, not a game at all. When we write about them, we say so plainly. Our comparison of Reflex, ReflexTest and RTap shows which one fits which kind of user.
How we check facts
App details change, so we work from the listings themselves: developer name, package name, version, size and price as shown on Google Play and established app directories. The current Reflex version we cover is 14.9, free, about 24.6 MB. If a detail on this site looks out of date, the Play listing wins — it is the source the developer controls.
Reaction-time numbers on this site come from well-established human benchmarks: about 250 milliseconds average for a visual cue, about 170 milliseconds for sound, and around 150 milliseconds for the fastest human reactions. We use those figures so your scores have context, not to promise you will hit any particular number.
What we are not
We are not Kranus Company, and we do not publish or distribute the Reflex app. Downloads happen on Google Play through the official listing, which our Reflex download page links to. We never host APK files here, and we do not link to unofficial download sites.
Everything here is free to read, and the site exists to save you the confusion we ran into ourselves: five apps, one name, and you just wanted to test how fast you are.