TL:DR; Secure-USB - a tiny, portable and easy-to-use file encryption software that implements strong 256-bit AES encryption to encrypt data.
Download Secure USB Shareware - Rating: 4.78
ttdsoft USB Pen drive Copy Protection and Encryption - for Any files , Any data , Any audio ,Any video, Any image file , Flash file features -Great feature- Anticloning , Manage - Protection | USE ANY MAKE of USB drive and ANY SIZE of pen drive
ttdsoft PDF Copy Protection Tools for Android is to prevent all your pdf files from unauthorized copy and distribution. Once protected (encrypted) using this software , protected PDF can be read from many medias such USB Drive OTG SD Card
It lets you password protect, hide, and encrypt data of folders in hard disk or portable disk. Without password, nobody is able to delete, move or copy the files in protected folders.