This may be a silly question, but I need to clarify before purchasing IP Phone devices.
My question is will any of Grandstream or any other IP Phone devices will compatible with FreePbx or are there any specific models or brands that are compatible with FreePbx?
I’m going to purchase Grandstream GRP 2615 with console and GRP 2602.
Typically any device that uses the SIP protocol should work in Asterisk (which is the component of FreePBX they connect to), so those phones should work.
The tricky part is really in figuring out how they are configured/provisioned by you for your environment. Sangoma Phone hardware typically has native provisioning for the phones built in. Other phones you are really on your own to figure out how to provision and manage.
The Grandstream GRP series works just fine with FreePBX. I have a few. One plus is that you can use the Grandstream GDMS provisioning system for free to set up and maintain the phones. No local provisioning from FreePBX is needed.