I too have been worried about that! They claim they'll offer a self-hosted version soon. I'd feel a lot more comfortable going that route so my IP is often from the same place.
Right now everything is running on their servers with god knows what IP addresses and from where.
So far I haven't been banned but I have had to reset my Facebook password once.
Instagram suddenly stopped working and I had to reconnect a few times.
So far WhatsApp is ok.
IMHO the iOS app is close to useless and I stopped using it.
The desktop app is where it's at and I'm only using that for now.