This app cant be replaced when it comes to chatting with friends, relatives, colligues etc. for free and also for voice chat and video calling.it works smoothly. I am using it for more than 5 years and I had no problem using it till now. I recommend it to everyone who hasnt installed it till now. It can also be very important if you are a student and need to send importamt pictures pf your notes to your friends. Because it is the best app when it comes to sharing picture, videos, music etc.