Google has updated the Hangouts iOS app to include platform-specific updates. The Hangouts iOS app now has the ability to make phone calls directly from the app. Incoming messages will no longer stop your music from playing. Animated GIFs also play in-line. By introducing phone calls, now users can call anyone they want in the U.S. and Canada for free.
For users that are outside of North America, international calls will cost a little bit per minute. The phone calls are powered by Google Voice.
The Google Hangouts app will let you make and receive calls. The outgoing calls will one from your Google Voice number and incoming Voice calls can be answered from Google+ Hangouts.
Animated GIFs will play in-line. If you are chatting with a family member or friend, you can insert a GIF and it will play right away without requiring the other user to click through to see it animate.
You can download the Google Hangouts iOS app from here.