First step
You and a friend need to agree on a password. Do this in a crowded cafe or smoky bar. DONT EMAIL OR TXT THE PASSWORD.
To send a secret message to a friend
Write a message in the box that is labeled "write message here"
Then, click the button below the txt box that is labeled "create secret message link"
(make sure you have entered the password twice, in the password txt boxes).
You should see a URL link (very long), in the txt box labeled "secret message link."
Click the "copy link" button. The link will disappear.
Paste this URL into an email, or txt, or chat box, so that your friend can get the secret link.
To decode a secret message sent from a friend
click on the URL link your friend sent.
You should see a webpage, and your link in the right text box
(you can also copy and paste the URL into the text box)
Enter your password (twice) into the password boxes
click the button with blue text "decode secret message link"
The link will disappear, but you will see decoded text at top of screen, in blue
If you get an error "414 Request-URI too long". Don't Panic.
Just select and copy the link and paste directly into the "secret link" box.
You can right-click on the link and choose "copy link address."
If you input the password correctly (twice), then the link will decode...
Notes
This web page uses SSL encryption and is completely client Javascript
-- nothing is sent to any server, including ellipticalcow.com
If you choose a strong password, then this app is reasonably secure1
it uses the Stanford Javascript Crypto Library (defaults)
text to hash | sha256
|
    | sha256("aaa") = 9834876dcfb05cb167a5c24953eba58c4ac89b1adf57f28f2f9d09af107ee8f0 |