iPlum mobile app is engineered for low bandwidth usage. It adapts to available data rates and latency of a broad range of Wi-Fi or cellular data channels, by controlling refresh rates and through efficient codec design. Calls are transferred seamlessly between Wi-Fi and wireless data channels as the user moves in and out of coverage zones.
If data is an issue you can setup Call Forwarding in the app & receive calls on any native mobile or landline number. You will not use data when receiving iPlum calls. It will be used only when you call-out using iPlum.