Need a hand with Entrain, have a question about a feature, or hit a problem with a purchase? We read every message and are glad to help.
We typically reply within a couple of business days. Please include your device and iOS/Android version so we can help faster.
For binaural beats, yes — each ear must receive a different tone for the effect to work. If you don't have headphones, use the isochronic presets (like "Unwind"), which pulse a single tone and work fine on a speaker.
For most people, yes — it's just sound. But Entrain is for relaxation, focus, and meditation support only. It is not a medical device and does not diagnose, treat, or cure any condition. Don't use it while driving or operating machinery. If you have epilepsy or a seizure disorder, are pregnant, or wear a pacemaker, talk to your doctor before use.
To restore a previous purchase, open the paywall in the app and tap Restore Purchases. To change or cancel an auto-renewing subscription, go to Settings → [your name] → Subscriptions on iPhone/iPad (or the Google Play Subscriptions screen on Android) — subscriptions are managed by the App Store / Google Play, not inside the app. The lifetime unlock is a one-time purchase and never renews.
Most apps hide the frequencies behind vague "sleep" and "focus" buttons. Entrain exposes the carrier and beat frequency in Hz, lets you build descent programs that glide the beat over a session, offers binaural, isochronic, and monaural modes, and synthesizes everything in real time — so sessions can be any length, work offline, and stay private.
A core set of sessions and the player are free. A subscription (or the one-time lifetime unlock) opens the full preset library and the custom frequency controls. You can try the full engine free in your browser at ericstevenson.com/entrain.
Entrain's frequency/use descriptions reflect general tendencies reported in peer-reviewed research on auditory-beat stimulation. These describe research findings, not guaranteed results, and individual responses vary. Key sources:
Entrain has no accounts and collects no personal data. See the full Privacy Policy.