Smilio

Hide your words behind the mask. Smilio is a fully offline secret-message studio wrapped in a dark Venetian masquerade aesthetic. Encode and decode text with six classic ciphers — Caesar Shift, ROT13, Atbash, Vigenère, Rail Fence, and Keyed Substitution — then share your ciphertext anywhere. Only the recipient who holds the key can unlock what you wrote. The star of the show is steganography: tuck a secret message invisibly inside a photo using LSB pixel encoding, save it to your gallery, and pass it on. To anyone without Smilio the image looks perfectly normal. Pick the photo back up at any time and Smilio surfaces the hidden words in an instant. Not sure which cipher was used? The built-in Cracker runs frequency analysis against any ciphertext and ranks the most likely Caesar shifts with side-by-side decoded previews. The Cipher Library walks you through how every algorithm works, complete with live try-it panels. Design polished shareable cipher cards, or browse your personal Vault of past secrets — everything stored privately on your device, never in a cloud. No internet required. No accounts. No tracking. Your secrets stay yours.