I work in finance and, for compliance reasons, we've been trying to stamp out employees using WhatsApp but it is basically impossible.<p>No matter how much we threaten disciplinary action in our handbook, people still use it, they just hide it more. Obviously we have no way of proving it, but we can see people doing it when the office is open. The financial regulator says we should use technology to reduce WhatsApp use - but given it's happening on personal phones, I'm not sure what we're supposed to do. Obviously nobody would accept company spyware on their personal phone.<p>Is there some solution to this issue that I'm missing?