One of the things that really grinds my gears is when I get sucked into group iMessage conversations that I really don’t want to be in. Although rare, sometimes people do it just to wish a bulk of people a good holiday without sending individual messages, but other times people do it just to be annoying.
Unfortunately, Apple makes things even more difficult on you by limiting the ability to leave a group iMessage conversation to when there are four or more people in it, so if you’re being dragged against your will into a three-way iMessage conversation, then you'll find the button to leave will be grayed out.
That’s where a new free jailbreak tweak called AntiSocial by Tony Kraft comes in handy, as it enables the "Leave this Conversation" button even when you’re in a three-way iMessage conversation.