Last updated: October 21, 2026
The short version: Reaction Light Trainer has no accounts and does not track you across apps. Your training data stays on your device. The free version shows ads through Google AdMob; a one-time “Remove Ads” purchase turns them off. We run no analytics SDK of our own, and multi-device sessions stay on your local Wi-Fi — nothing is sent to our servers. The only information we receive is what you type if you choose to contact us, and — only if you opt in to the Leaderboard or Online Duel — a nickname you choose plus your assessment scores.
Your training history (sessions, reaction times, scores) and app settings are stored locally on your device only. They are never uploaded. Deleting the app deletes this data.
In multi-device mode, your phones and watches discover and connect to each other directly over your local Wi-Fi network (using Bonjour and a peer-to-peer connection). Session data — which light is lit, taps, scores — travels only between your own devices on your own network. It does not pass through, and is not stored on, any external server.
These two features are opt-in and need an internet connection; everything else in the
app works without them. When you first use one, the app generates a random identifier
on your device and asks you for a nickname. We store on our server
(reactionlight.100for1.com, operated by us): that random identifier, your
nickname, the results of the Standardized Assessments you choose to submit (average and
fastest reaction time, hits, errors, misses, accuracy, score, grade), the app's language
and platform, and — for an online duel — the room code and both players' results for up
to 30 minutes. No account, email, phone number, name, location, or device identifier of
any kind is collected. Your nickname and scores are visible to other players on the
leaderboard. Deleting the app discards the random identifier; to have your scores removed
from the leaderboard, contact us with your nickname.
The free version displays ads via Google AdMob. To show ads and measure them, AdMob may process device and usage information such as a device identifier, coarse/approximate data, and diagnostics, as described in Google's policies. We do not show the App Tracking Transparency prompt and do not track you across other companies' apps or websites; ads are contextual and use Apple's SKAdNetwork for privacy-preserving attribution. See Google's advertising policy. A one-time Remove Ads in-app purchase disables ads entirely.
“Remove Ads” is processed by Apple; we never see your payment details. The ad-free entitlement is stored locally on your device.
If you use the optional “Contact Us” form, we receive the email address, subject and message you submit, and we use them solely to respond to you. We do not add you to any mailing list or share this information with anyone.
The app is suitable for all ages. Because we collect no personal data, no special handling of children's data occurs.
If this policy changes, we will update this page and the date above.
Questions? Email zachsong@gmail.com or use the contact page.