Various encryption algorithms are available, e.g., AES, Blowfish, RC6 256 bit, and Serpent. You can protect your file(s) via zip with password. See following.
Protect via containers, e.g., zipped
The formats are zip, rar, 7z, tar, others. The recommended apps are B1 archiver, MiXplorer Silver, RAR, WinZip, and ZArchiver (ref. 2). These are paywares (i.e., software where payment is required), while WinZip is shareware (i.e., basic free features, with paid add-ons) and ZArchiver is still a freeware. For WinZip and ZArchiver, you will need to allow them access to your phones folders and files.
Samsung phones with Samsung My Files
If your phone has a File Manager, e.g., Samsung My File version 13.1.01.321 by Samsung Electronics Co Ltd, then you can compress your file(s) with password for added protection.
Go to My File > Select the file(s) to compress > Click the Menu icon > Select Compress > Rename the zip file > Check “Protect with Password” > Key in the password. Samsung did not specify what encryption algorithm they used and there was no verification of input to password (so you have to ensure that you don’t accidentally miss a key or two, but you can opt to visualize the input to verify entry).
Reference
- Six best free Android File Encryption Apps, undated (https://listoffreeware.com/best-free-android-file-encryption-apps/)
- Five best zip, rar, and unzip apps for Androids, 24 Jan 2022 (https://www.androidauthority.com/the-best-zip-and-unzip-apps-for-android-258692/)
- How to zip files on your computer or phone to save space, 20 Jul 2021 (https://www.businessinsider.com/guides/tech/how-to-zip-a-file)
SKC SCI 