How to make a conference call on your iPhone with up to 5 participants

You can place a conference call on your iPhone from the Phone app, and then add up to five total participants.
Under30CEO on MSN

How to Make a Conference Call on iPhone: Step-by-Step Guide

Making a conference call on your iPhone can be simple and effective. Whether you’re connecting with friends, family, or ...

How to record an incoming or outgoing phone call on your iPhone using third-party apps

You can record a phone call on your iPhone using third-party apps — but currently, there's no built-in way to record a call.
MacRumors

WhatsApp Can Now Be Your Default Call and Messaging App on iPhone

WhatsApp can now be selected as the default calling and messaging app on iPhone, if users so wish (via WABetaInfo). A change in the latest version of WhatsApp available on the App Store (v25.8.74) ...