Awesome app for free internet call from any where to any mobile operator, it supports 4G LTE and VOLTE enabled devices.
The app is user friendly and uses less memory, GUI can be developed., the dialer is also a good replacement for inbuild dialer.
Besides free internet calls, free messaging and video call is also an advantage.The option to use sim other than jio is a good feature
However, it sometimes loses signal during call in certain areas which is a drawback but its rare.