Google+ Hangouts for iPhone and Android Devices

Google+ Hangouts brings your conversation to life.
Hangouts brings one on one and group conversations to life with photos,emoji and video calls for free.
Connect with friends across computers,Android Devices like Samsung android mobiles (samsung galaxy grand,samsung galaxy S3,samsung galaxy S4 and etc ) and Apple Devices like iPhone,iPad and iPod.
When they are typing or whether they have seen your message.
We can turn any conversation into a video call with up to 10 friends and message friends even if they are not connected.

                   
Hangouts stay in sync across devices so you can start or continue them anywhere.
We can save the chat history, including shared photos and your video call history.Get notifications just once. Once you see an alert, you won’t see repeats on your computer or other Android devices and Snooze notifications at times when you’d prefer to be undisturbed by alerts.

     
Download :

Note:
The drawback is it doesnt support "invisible" status.

 How to use Google Hangouts in iPhone:

Step 1:  Open Google+ Hangouts  from your device

Step 2:  Login to your account

Step 3: This  is your welcome screen

 

Step 4: Skip this step to verify your mobile number

Step 5: Choose the person to whom you want to chat

 

Step 5: Now you can chat with your friends, to send photos click on the camera icon , to make the video call click on video icon and to add the more people click on  person icon.