A light you keep your eyes closed for
Eidovelle pulses the torch on the back of your phone while you lie down with your eyes shut, and carries music and a voice through your headphones for as long as the voyage runs.
Some people see moving geometric colour through a closed eyelid. Some see very little. There is no way to know in advance which you are, and neither one is the wrong result.
18 and over, after screening. iPhone only at launch. Android is being built. Read the safety information first.
Lie down somewhere dim, and close your eyes
Prop the phone so the light on the back faces you, put headphones on, close your eyes.
For the next five to thirty minutes the torch pulses, the score moves with it, and a voice tells you where you are. Your eyes stay closed the whole way, which is how it works rather than a way of making it gentler: a closed eyelid spreads light across more of the retina, not less.
There is a stop under your hand the entire time. Touch the lower half of the screen and the light goes out at once, with nothing to confirm. The first voyage makes you use it once, on purpose, so your hand knows where it is before you need it.
Some people get very little out of this. The light runs the same for everyone.
Twenty places, each one built as a piece
A world is a place rather than a preset: named, painted, scored and narrated as one thing. Each is built for its own set of lengths, between five and thirty minutes.
- The Ascent The first climb. It is the one that teaches the stop control by making you use it. Free, always.
- Undersong Reef A reef of light a long way under the surface. Free, always, so the whole thing can be judged before any of it is bought.
- Eighteen more Ballast Hold, Bell Quarry, The Bottle Kiln, The Drying Loft, Hard Ground, The Icefall, The Lee Wall, The Lock Chamber, The Long Weir, The Orrery, Plumb Line, The Reservoir Roof, and the rest. Five of them are free in any given week, and which five is worked out on your phone from the date rather than fetched from us.
A score that is not one track trimmed to fit
Each world is built from loops whose lengths share no common factors, mixed against the same clock the light reads. The combined cycle is longer than the longest voyage, so the fifteen minute version and the thirty are the same music at different rates, and no two runs sit the same way.
Every world without light
Same music, same narration, same lengths, dark screen. This is a full line of the product rather than a consolation prize, and it is what the whole library becomes for anyone the screening closes the light to. It costs the same. A cheaper audio tier was considered and rejected, because it would have priced people by their medical history.
A private atlas
After a voyage you can log what you saw. Entries are named by world and date. The picker's options are not a description of what a voyage produces. The atlas never leaves your phone.
There is no light on this website
Nothing here flashes, pulses or strobes. There is no motion anywhere on this site, no animation in any stylesheet, and no script on any page at all.
A web page has nobody screened in front of it. Anyone can arrive at one, at any age, in any state, by accident. So the light lives behind the screening, inside the app, or it does not run at all.
The light is not for everyone
Before the torch pulses once, the app asks about seizures, photosensitivity, eye closure, family history, and the symptoms that most often go unrecognised: an unexplained blackout, a lapse in awareness, jerking of the arms or head in the first hour after waking. One episode is enough to answer yes, and Unsure is counted as a yes on every question that closes the light.
A yes to any of the first five closes the light on that phone. There is no button that says you accept the risk, and no version of the light we will sell past that point. What no app can do is stop a person answering the questions a second time with different answers, or deleting it and starting again. The screening works on people who answer it honestly.
The numbers are in the binary, not in the content
The light runs between 0.5 and 13.0 Hz and never enters the 13.5 to 25 Hz band, where published guidance puts the risk highest. Modulation depth is capped at 0.85 of full and torch level at 0.6 of maximum. Unbroken flicker is capped at twenty minutes. Nothing shipped later, and no mistake made later, can ask your phone for a value outside that envelope.
The band Eidovelle does use is not a band without risk, and the top of it sits inside the wider range published sources treat as capable of provoking a seizure. Where each of those limits comes from, which of them rest on published sources, which are our own judgement, and what moved on 22 August 2026, is set out in full on the safety page.
What stays on your phone
This version of the app makes no network requests. There is no account, nothing to sign in to, and no request that leaves the phone carrying anything you did. The only traffic is Apple's own, when you buy something or restore a purchase, and that is between your phone and Apple. A later version will add two quiet exceptions, both described in the privacy policy before they arrive: downloading new worlds, and an anonymous once-a-day message of whole-number counts, with no identifier of any kind and an off switch in Settings.
Your screening answers are not written down at all. The outcome is, and it stays on the phone. So does your atlas. No advertising identifiers, no tracking, nobody watching a session.
Everything a voyage needs is already on the device, so a voyage runs in aeroplane mode, on the free worlds as well as the paid ones.
The app asks for camera permission, and it should say why: on iPhone the torch holds steady timing only while a camera session is open. Nothing is recorded, seen or saved.
What it costs
The Ascent and Undersong Reef are free, with no time limit, at every length they were built for, in the light version and the audio version alike. If we ever have to change how the library is sold, anyone who already has those two keeps them.
Everything else is a subscription: $4.99 a month, or $34.99 a year with the first 21 days free. Both renew until you cancel, both are charged to your Apple Account, and cancelling is what stops the charge. Five more worlds are free in any given week without paying anything.
There is also Founding, at $99.99 once. No renewal, no expiry, every world we ever publish. It is a one-off purchase in the app rather than a subscription, it is offered while it is offered, and if it is withdrawn everyone who bought it keeps it. It exists to pay for product liability cover and for legal review, which are the two things one person cannot pay for out of pocket and the two things we are not willing to ship without.
Everything is bought inside the app, through Apple. Refunds are Apple's to give, through Report a Problem in your Apple purchase history. The screening runs before the app offers anything for sale, so nobody pays before finding out whether the light is open to them, and if it is not, every world still plays as audio at every length at the same price.
Two things to be true
- I am 18 or older.
- I have read the safety information and none of it applies to me.
This website never asks you a health question, because health answers should not travel. The screening runs in the app, on your phone, where the answers stay. Ticking a box is not the screening. It comes before it and it does not stand in for it.