This is my favorite application for contacting with relatives and business partners. I believe there is nothing more convenient than whatsapp. here is pretty convenient to create group chats where you can not only chatting, but also make a group call. I believe nowadays when all people are on a remote job, it’s pretty helpful to use such applications as whatsapp. Moreover, it relates to the facebook, one of the biggest IT companies in the world. It makes this application twice more reliable and you understand that all of your data is protected. Guess that there is no good substitution for whatsapp up to date.