ESI Ditto is a mobile SIP endpoint for use only with ESI IP-PBX phone systems. Ditto leverages the flexibility of a iOS devices with the power of an ESI desktop phone to allow road warriors and other on-the-go types to make and receive business calls from anywhere; over WiFi, over the cellular network, or (if your carrier supports it) over the 3G / 4G cellular data network all while maintaining a single office phone number and voicemail.

ESI Ditto's powerful WiFi quality-monitoring algorithms will automatically hand calls off from WiFi VoIP calls to normal cellular calls when the WiFi coverage begins to degrade. With Ditto you can easily move calls between Ditto and your ESI desk phone, dial other user extensions, and even transfer calls to a remote location using Esi-Link networking. ESI Ditto mirrors the functionality of your ESI desk phone right on your iPhone or iPad.