Use your old android phones as pager (1 reply)

had some old android phone and tablets. still working well. it would be a big waste if throwing out.

Found below article, convert them to pagers, put one android into every room. working perfect!, but you should have a raspberry pi 3/4 and install freepbx on it first


Reference:

https://www.cosfone.com/a-free-intercom-paging-system-with-raspberry-pi-and-old-android-phones/