ONCALL PBX is a powerful Sip-based softphone designed specifically for iPhone users. With the ability to make and receive calls, as well as send and receive instant messages, this app provides a convenient and efficient communication solution.

One of the standout features of ONCALL PBX is its compatibility with the Oncall System, allowing for seamless integration and enhanced functionality. The app supports push notifications, ensuring that users never miss a call or message, even if the app is force terminated.

Utilizing the iPhone's existing contact list, ONCALL PBX makes it easy to communicate with multiple contacts. The app offers a range of call features including call switching, call merging and splitting, and attended and unattended transfers. Additionally, it supports video conferencing with MCU support, enabling high-quality video calls up to 1080P with H264 and VP8 codecs. HD audio calls are also supported, ensuring crystal-clear voice communication.

Overall, ONCALL PBX is a reliable and feature-rich softphone app for iPhone users, offering a comprehensive communication solution for both personal and professional use.