You can make both voice and video calls, form chat groups, share photos and videos, use stickers, among other functions. You can also use it on your tablet.
You may also be interested in this article on how to make free calls from your cell phone.
As its name suggests, using imo free video calls and chat for , you can participate in free video, voice, and group calls with your loved ones. The app also lets you exchange unlimited text messages over your 2G, 3G, 4G, or WiFi connection. And the best part is that the person that you're communicating with can be using any device as long as it supports these features.
To liven up your conversations, there are hundreds of free stickers included in the app. Plus, the application's encryption capabilities are reassuring that all of your communications are secure.
Imo is also available for iOS devices from the App Store.