ESI mPhone™ is the latest addition to ESI’s line of award-winning SIP-based softphones. As the market leader of desktop phones and mobile VoIP software products and solutions, Estech Systems, Inc. (ESI) has created the ESI mPhone™ application for the ESI IP Server 900™ business phone system, including ESI mPhone™ Push Service.

* ESI IP Server 900™ phone system running software version P4.3.x or higher
* SIP station licenses on the system for each user
* SIP station user MUST be set to a Remote SIP Station

ESI's mPhone™ turns your tablet or smartphone into an extension on your ESI IP Server 900™ phone system, allowing those on-the-go employees to make and receive business calls from anywhere, while maintaining a single office phone number and voicemail.

* Make and Receive calls with your office phone number
* Calls made with your mobile extension show your office caller ID
* Place calls on hold
* Transfer calls to other company or public numbers
* Make calls over remote WiFi or 3G / 4G / LTE
* Highly secure, SIP-based softphone with exceptional voice quality
* Multitasking support for background operation, such as fielding incoming calls while using other applications and Push Support
* Supported accessories include headphones, AirPods & other Bluetooth™ devices
* IPv4 & IPv6 support

For more information on the ESI mPhone™ application, please visit:

Some mobile network operators may prohibit or restrict the use of VoIP functionality over their network and may also impose additional fees, or other charges in connection with VoIP. You agree to learn and abide by your cellular carrier's network restrictions. Estech Systems, Inc. (ESI) will not be held liable for any charges, fees or liability imposed by your carrier for use of VoIP over Mobile/Cellular Data.

Emergency Calls
The ESI mPhone™ mobile product provides handling designed to redirect emergency calls to the Native Cellular Dialer when possible, on a best reasonable commercial efforts basis. However this functionality is also dependent on the operating system of the mobile phone, which is outside of ESI’s control and is subject to change at any time. As a result, the official position of Estech Systems, Inc. is that the ESI mPhone™ product is not intended, designed, or fit for placing, carrying or supporting Emergency Calls. Estech Systems, Inc. (ESI) will not be liable for any costs or damages arising, either directly or indirectly, from the use of this software application for Emergency Calls.

What’s New

Version 5.5.5001

Stability and performance improvements
This version contains improvements to the overall stability and performance of mPhone and miscellaneous bug fixes.

Ratings and Reviews

3.1 out of 5
8 Ratings

8 Ratings

GC8926 ,

Will not allow incoming from office

The only way it allows incoming calls to the app is if my phone is open and on the app. Pointless for incoming.

App Privacy

The developer, Estech Systems, Inc. (ESI), has not provided details about its privacy practices and handling of data to Apple. For more information, see the developer’s privacy policy.

No Details Provided

The developer will be required to provide privacy details when they submit their next app update.


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