I have one customer using mlc. At least they have it, but for some reason they're not utilizing it. After initial setup by me, they dont seem to want to use it. That said, I thought it would be pretty handy to have. Maybe it's a matter of management requiring its use, or providing the cell phone so he can require users to use it.
We haven't tried it outside of the wireless lan network. I think the success depends a lot on the wifi connection throughout the building.
When installing the app, only activate once per cell phone! If something doesn't work, its not the app, it's a setting somewhere. If you activate more than once, you'll eat up your license count. It's a pita and takes days to get NEC to get them cleared out.
Jim