Mobile device connections work well enough -- a reliable VOIP app on Android was constructed with the DropFrog service on the backend. Generally, a network connection can get dropped on any device even for a "server" device; it is a failure case to anticipate and program accordingly. On DropFrog, by the way, the channel continues to exist if there are any participants and also for half a minute with no participants whatsoever, anticipating and accommodating failure cases. For the browser (and more) consideration, WebSockets under control of the application programmer makes the most sense, fulfilling the requirements of a persistent and secure connection (WSS). WebSocket support will be added in the future.