This makes a link. Whoever opens it reads your letter by dragging a finger across it, and every word burns as they pass. There is no second read.
The key stayed on this device and was never sent anywhere. The server is holding something it cannot read.
Tells you when the letter has been opened. Don't send it to them.
Put your finger on the pulsing circle at the top left and drag slowly to the right. The words light up just above your fingertip, then burn out behind you.
At the end of a line, drop down to the next. You get one pass — and if you leave this page, the rest goes with you.
Nothing was kept. There is nothing to go back to.