Text Encryption
Text encryption can be useful for different purposes. There's the "easy hiding" of spoilers (e.g. using Caesar-Chiffre aka "ROT-13", also used with Geo-Caching), or Morse-Codes. And there are more serious things like safe-guarding sensitive information with real encryption. For all this, you can find matching Android apps:
Caesar-Cipher
Caesar-Cipher is also known as "ROT" (from "rotate"), as the algorithm rotates the letters of the alphabet (e.g. 13 times with ROT-13), which is easily revertable. Caesar is said having used this to encrypt military correspondence, hence the name.
- Rot13 ↺ Edg13 (5@4) 0 LastUpdate: 2017-03-15
- CaesarCipher (5@1) 0 LastUpdate: 2019-10-22
- Caesar Cipher Disk (4.8@200) 1 LastUpdate: 2021-08-09
- ROT13 Translator (4.8@100) 0 LastUpdate: 2014-07-20
- Caesar cipher - De-/Encryption (4.5@248) 2
- Pijaret (0@0) 0 LastUpdate: 2016-09-27 Github
Morse Code
Morse code was used for telegraphy long ago. But it's still active in seafaring today (often as light signals), its best known example probably being the SOS distress signal.
Morse Tutors
- Morse Mania: Learn Morse Code (4.9@28,446) Ǥ 9 2
- Morse Trainer (4.5@6) 0 Github
- Morse Mentor (4.4@348) 4
- G0HYN Learn Morse (4.4@104) 1
- Morse code - learn and play (4@771) 6 2 LastUpdate: 2020-06-05
- Mors. : The Morse Code Trainer (3.3@388) 2 1 LastUpdate: 2020-06-15
- Morse Audio - Morse Code Learn (1@42) Ǥ 3 1 LastUpdate: 2018-12-03
- Dahdidahdit (0@0) 4 Github
General Morse apps
- Morse Code Translator (4.8@96) 4 1 LastUpdate: 2021-12-12
- BF4 Lantern & Morse Solver (4.7@1,232) 4 1 LastUpdate: 2020-07-21
- Morse (4.6@40) 3 Github
- Morse Code (4.3@7,774) 7 1
- M³ Translator: Morse code (4.3@5,355) Ǥ 12 2
- Pocket Talk (4.3@6) 5 LastUpdate: 2016-01-13
- Morse Torch (4.1@19) 2 LastUpdate: 2018-11-30
- morsee : Enjoy Morse code (4@1,273) Ǥ 7 4
- Morse Code Reader (3.9@2,026) 2
- Morse Transmitter (3.8@1,093) 1 LastUpdate: 2014-01-20
- Morse (3.7@1,761) 5 2 LastUpdate: 2018-03-10
- Morse Code Translator (3.6@2,895) Ǥ 12 3 LastUpdate: 2022-12-14
- Morse Me (3.5@87) Ǥ 9 4 LastUpdate: 2020-05-28
- SMS-Morse (1@20) 0 LastUpdate: 2022-04-07
Morse Keyboards
- DotDash Keyboard (4.3@282) 1 LastUpdate: 2020-05-20 Github
- MouseCode Keyboard (4@5) 1 LastUpdate: 2017-03-01
- Morse Code Keyer (3.6@178) 4 1 LastUpdate: 2020-02-23
- Morse Code Keyboard (3@141) Ǥ 5 2 LastUpdate: 2018-12-08
Multiple text-encryption methods
- Coooder (4.7@6) Ǥ 5 4 LastUpdate: 2019-02-09
- Cipher Decoder - Cipher Solver (4.5@2,599) Ǥ 7 4 LastUpdate: 2019-05-15
- Cryptography (4.4@3,386) Ǥ 8 2
- Decrypto (4.3@3,943) 4 1 LastUpdate: 2017-11-10
- Cipher Solver (4.2@188) 0 LastUpdate: 2016-11-10 Caesar, Vigenère …
- Universal Encoding Tool (4@141) 0
- Cryptography Mean™ - Encryptio (1@5) Ǥ 5 1 LastUpdate: 2018-07-24
Text encryption with PGP
- Latebra cryptographic app (4.6@8) 17 2 encrypt SMS/Email
- OpenKeychain: Easy PGP (4.3@4,191) Ǥ 19 Github; Howto 12/2017 | 2/2019; Anleitung 8/2020 | 11/2020; Wikipedia DE | EN
- APG (4.2@13) 6 LastUpdate: 2014-04-04 Github; Description and Howto; Wikipedia (EN); Files + Mails
- Tessercube (1@30) 20 LastUpdate: 2020-07-25 Github
- OkcAgent (0@0; ~EUR 1.00) 3 1 LastUpdate: 2020-11-24 Github; make OpenKeychain available in your Termux shell
Encryption with AES/DES
- AES Message Encryptor for SMS (5@157) 0
- Cryptool (4.8@223) 9 Github
- Private Notepad - safe notes (4.3@48,938) Ǥ 16 4
- SSE - File & Text Encryption (4.3@3,823) Ǥ 6 GitLab; Password-Safe, texts, files, and more; cross-platform (Windows, Linux, Mac OS X, …); Open Source
- Notepad with password (4.3@3,704) 9 4 / Notepad with password PRO (4.1@105; ~EUR 4.50) 2 LastUpdate: 2019-10-26
- SealNote (4.3@3,157) 2 LastUpdate: 2017-04-13 Github; Video Intro 4/2017
- Sec Notes- Secure Notepad (4.1@1,534) Ǥ 17 2
- CrocodileNote (3.5@16) 2 LastUpdate: 2015-03-13 Github; AES-256 encrypted notes
- SimpleTextCrypt (0@0) 0 Github
- DroidCrypt (0@0) 4 Github; files & text with AES
- Encrypt Text (0@0) 0 LastUpdate: 2020-08-23 Github
- KeyCip (0@0) 7 LastUpdate: 2022-07-17 Github
Various other encryption apps
- Crypto - Encryption Tools (4.6@1,806) Ǥ 11 3
- Latebra cryptographic app (4.6@8) 17 2 encrypt SMS/Email
- Enigma Simulator (4.5@2,188) Ǥ 6 1
- Safe Notes is a secure notepad (4.3@5,275) Ǥ 12 2
- Oversec (4.3@260) Ǥ 4 LastUpdate: 2019-04-23
- Enigma Trial - Cryptograms (4.3@182) 0 LastUpdate: 2017-12-09 / Enigma - Cryptograms (4.4@172; ~EUR 1.00) 0 LastUpdate: 2017-12-09
- Cryptogram Puzzle Quotes Game (4@1,507) Ǥ 5 3 LastUpdate: 2020-04-26
- PixelKnot: Hidden Messages (3.2@1,186) 3 Github; Details; Steganography (text hidden inside image, unlock with passphrase)
- Encrypt Editor (1@35) 5 2
- Secret Encrypted Keyboard (0@0) 1 Github; Keyboard for secure E2EE communication
- Rivia (0@0) 0 LastUpdate: 2022-09-02 Github
- EnigmAndroid (0@0) LastUpdate: 2019-01-03 Github; Enigma Simulation
Further Readings:
- Category Encryption of Files and Folders
- Category Messenger & Conferences