By default, everyone on WhatsApp can see when you're using the app. If someone recently messaged you and sees you're currently online, they may think you're avoiding them if you don't respond right away — especially if you don't share read receipts. However, you can block them from seeing your online or last seen status and apply it to everyone or just specific contacts. WhatsApp has had its last seen feature, which shows other WhatsApp users the exact time you last used the app, for a long...