Burner is an app for your “other” number – your work number, Craigslist number, Etsy number or dating number – the one to give out when you need to be in touch, but want the option to disconnect.

Free dial in and video conferencing. I have used the free dial in tool and it works great! 

Features customer service reviews, database of company phone numbers that reachhuman customer service reps, and a weblog.

This video calling app also allows for voice only calls (switch the toggle at the top to audio-only calling). 

Provides a U.S. telephone number, chosen by the user from available numbers in selected area codes, free of charge to each user account.

Hushed puts a private, disposable communication in your hand. Private messaging, voice calling, texting, voicemails, and more in a simple & secure app.

Lock your child's phone until they call or text you back.

This app provides toll-free numbers in addition to local lines.

Tetra uses AI to take notes on phone calls. 

This app has some great features such as being able to search and identify  any phone number, block unwanted calls and seeing when your friends are available. I personally like the spam ID feature that filters out spam phone calls.

Stress-free conference call service. Never need a PIN. Never ask "who joined" or "who said that?" Also includes a screen share feature.

Free messages as well as make free calls to other Viber users, on any device and network, in any country.

Mobile messaging app which allows you to exchange messages without having to pay for SMS. Includes international messaging.