A build system and primary set of packages for Termux
Termux is an Android terminal emulator and Linux environment app that works directly with no rooting or setup required. A minimal base system is installed automatically - additional packages are available using the APT package manager. Access remote servers using the ssh client from OpenSSH. Termux combines standard packages with accurate terminal emulation in a beautiful open source solution.
...This handy bash script helps you to backup and restore the last modified timestamp for folders recursively.
If you want to use an android native app, there's File Timestamp, however the txt format is different.
https://play.google.com/store/apps/details?id=br.com.pogsoftwares.filetimestamp