Everyone knows this, everyone uses this and everyone loves it. It has been a revolution in messaging when it was introduced, now it has introduced voice and video calls subsequently. Being able to send different files is a bonus in any way. Groups on the other side are a game winner, being able to spread a message to 256 simultaneously is just amazing. User interface is as simple and useful as it gets, can’t think of something simples than this, because of its simple design, its data comsumption is very low. These days, hardly any phones remain without the install of whatsapp. Just amazing