We have an on prem. version of 3cX. it is so versatile. Everyone can use it from where ever they are. So long as you can see the internet some how, via home wifi, 4G/5G phone or cabled network in you office/home you can use 3cX to make a call or video conference be it one to one or in a group. You can use your laptop or you mobile or even a handset. all of which are simple to configure and use.