ECO

ECO plays you a sequence. You play it back. Every level adds one more step and
the playback gets a little faster.

That is the whole game. What makes it ECO is how each circle tells you who it
is.

THREE CHANNELS, ONE MEMORY

Every circle is three things at once, not one:

• A TONE — Do, Mi, Sol and high Do. Four notes of a pentatonic scale, so any
sequence the game throws at you still sounds like music instead of an alarm.
• A WAVE — 3, 4, 5 and 6 lobes. When a circle fires, the ripple that travels
across the screen carries its own number of lobes. You can recognise it from
the corner of your eye.
• A VIBRATION — 30, 55, 90 and 130 ms. Four lengths you can tell apart with
your thumb.

That is not decoration. It means you can play ECO with the sound off on a bus,
with vibration off in a meeting, and without depending on colour to tell the
circles apart. Three ways in, and you only need one of them.

FAIR ON PURPOSE

• During playback your taps are IGNORED, never counted as mistakes. A rushed
finger costs you nothing.
• The touch area is bigger than the drawn circle. Missing by two pixels should
not end a run.
• The same circle never comes up twice in a row — two in a row are remembered
as one and the level would be free.
• The circles live in the lower half of the screen, where one thumb reaches
them comfortably with either hand.

WHEN IT GOES WRONG

Miss a step and the wave collapses instead of just turning red — the shape
breaks, so you can see what happened. You can watch an ad once per run to
continue on the SAME level with the SAME sequence, replayed from the start. Not
a new pattern, not the next level. Where you were.

WHAT'S INSIDE

• Endless levels: one more step every time, playback speeding up as you go
• Score, best score and top level reached, saved on your phone
• A screen that explains the three channels, with the exact frequencies
• 18 languages, switchable from settings
• Accessibility: reduced flash, reduced shake, reduced particles
• Sound and vibration switches, plus a volume slider
• One finger. Portrait. No account, no sign-up, no internet needed to play

NO NOISE

No background music — this is a game about listening, and music on top of it is
just an obstacle. No forced full-screen ads. Real money buys nothing that
changes the game. Your progress is saved on your phone and nowhere else.