Not all of the popular messengers in the table can do calls. All of them can send text messages (some sort of chat). All of them have mobile clients. Many of them offer advanced functionality like sharing files, photos, video and audio messages. Only some of them can do calls. In fact, two of the most popular of them (WhatsApp and Facebook Messenger) do not. A separate table should be created for software to do calls. It's a different category.