I use WhatsApp every day. And I consider it the best.
It has helped me out more than once when traveling, when you can use Wi-Fi to call, send photos. Yes, you may say that all this can be done via Skype, but I don't have a front-facing camera on my phone and the meaning of such communication is lost.
And via WhatsApp, you can send your own voice recorded in a message, a video from a vacation, or those events that you want to share with someone else. For example, my brother sent me a video from the wedding via WhatsApp. And in communicating with relatives from Poland, this is generally super, because the difference in time zones does not allow you to communicate often on Skype, and so you can constantly keep each other up to date with all events.
In addition to such photo messages, this is of course the usual correspondence. Long days, nights, and days. Most often I communicate with close friends and relatives.
On the account of calls, for some reason, when you talk for a long time, the connection is constantly interrupted and you constantly have to call back.What else I really like is the privacy of conversations. And the fact that the app is absolutely free!
Instagram has become a source of income for many bloggers. Owners of popular accounts advertise products and services and get paid for it.
Many organizations also have their own accounts. They publish corporate news and present products. Thanks to comments, they get feedback from customers.
Some time ago, Instagram announced that the number of likes would not be displayed under publications. There are concerns that many users get upset when they get few likes. Although, not all the users were happy about this decision.