Consumer Reports: “Here’s what they’ll see on text messaging, Facebook Messenger, Instagram, LinkedIn, Signal, Twitter, and WhatsApp. If you’ve ever been bombarded with incessant messages on your phone or favorite social media app, or received even just one message from someone you’d rather not hear from, blocking the sender might seem like the obvious decision.  But blocking works differently in different apps. Some apps prevent people you block from sending you messages altogether, which makes it clear to the sender that you’ve blocked them. That could be good if a person (or company) is filling your phone or messaging app inbox with spam, like sketchy links for cash rewards or refunds. On other platforms, the sender might never know they’ve been blocked, though they may catch when you never respond to their messages. This might be an advantage with a casual acquaintance, like the person you met once at a potluck who keeps sending you news articles you’ve already seen. You’d rather not read them, but you want to avoid hurting the sender’s feelings. Whether you want to block someone in a stealthy way or an obvious one, you’ll need to know what happens on each platform or service. If you block someone, what does it look like to the sender?  I spent a week blocking and unblocking my Consumer Reports colleagues, and asking them to block me, to better understand how the feature works on seven different platforms. I think they unblocked me after the testing, but for some apps I can’t be sure. Down below, we’ll look at each one. But first, here are two caveats. First, sometimes muting is better than blocking. This will stop you from getting notifications when the other person sends a message, and some apps will put their messages in a separate folder or tab in the app. But you’ll still be able to read their messages if you want to, so you can catch up on your sister’s food photos before giving her a phone call, even if you don’t want to see them every day. From a safety perspective, it may also be better to mute someone rather than blocking them if they’re sending harassing messages. That will give you evidence of the harassment in case things escalate. Secondly, you might need to turn off read receipts. That’s because if you have it enabled, the person you’ve blocked might quickly notice that you haven’t read any of their messages. That could tip them off . We’ll describe how to check or change this setting for each app…”