Free open source clone of Help Scout: help desk, shared mailbox, email management and analytics. FreeScout is a pure PHP7+MySQL application which can be easily deployed even on a shared hosting.
I love Freescout, Use it for multiple clients.
One downside is that the app is just the website on your phone and does not really work well.
It works but not as an App experience.
For the rest they do awesome and developing in it works good!
