Once this feature is enabled, there are three new tabs, one for calls, chats, and contacts. The feature set is pretty straightforward. But you can switch to speakerphone or mute your microphone if needed during a call. Why this matters: Add WhatsApp to the strong group of contenders offering free phone calls for your Android device. Facebook also provides calling within its Messenger app, a full-blown platform. And don’t forget about Google’s Hangouts, which also comes with Android.
