Hi there,
We've also seen the same with our Samsung devices, but they are running on Android 5.1.1.
On our LG devices with Android v7 on with MiCollab running on 5GHz Wifi and 4G, we haven't seen a problem in testing so far, although it really does depend on cellular coverage.
One fix I looked at for this but was more complex, was create a VPN tunnel from the device onto a OpenVPN server with an always on connection, this helped us in the sense it was purely using cell data for MiCollab but the connection was always open, so it wasn't dropping. Not a perfect solution, but if you have the tools available it's a good experiment, plus it gives you a kind of MDM facility too.
Cheers
Steve