Open with something the room can answer in a few words, and tie it to what's already on screen. That one habit gets more replies than any clever line.
What should I say first in a busy group room?
Reply to a message that's already there instead of announcing yourself. In the main lobby of the free chat, text moves fast, and on a phone a standalone "hey everyone" can scroll off the screen before anyone reads it. Someone posts "power's out again, typing on 4% battery," and you answer with "storm or the usual roadworks?" That's an easy way into a conversation people are already having. The person you replied to has a reason to answer, and other people can see the thread and join in.
In the interest chat rooms, a room-specific question works better than general small talk. In the gaming chat, "what's everyone playing tonight, and was it worth the download size?" gets answers. In the music chat, "last album you played start to finish?" usually does too. In the place-based rooms, small local differences get people talking. In the UK chat, asking whether anyone else's train got cancelled this morning will pull in a few people. In the USA chat, a time-zone question works better, because some of the room is waking up while others are winding down.
Why does nobody answer my opener?
Usually the opener gives people nothing to work with. "Hi," "anyone here?" and "so bored" are the messages most often left hanging, because replying means the other person has to start the actual conversation. Turn it into a question with something attached: "bored, need a show recommendation that isn't a crime documentary" gives people something to answer.
Sometimes it isn't your fault. The user list can look full while the room is quiet. People leave tabs open, phones lock with the chat still loaded, and some regulars only read. During those stretches, reposting the same opener every minute makes things worse, because it starts to look like spam and gets you blocked by people who might have answered later. Post once, wait a few minutes, then reply to whoever speaks next. Your chat name matters too. A random string of letters and numbers reads like a bot. A simple name hinting at an interest, like "slowcooker_sam," gets replies from people who are curious about it.
What works when opening a private message?
Mention something the person said in the room. "Saw you mention learning bass in the music room, how long have you been at it?" shows you were paying attention. Compare that with the private messages that get closed right away: "hi," "wru from," "u there?" Those arrive in bulk, and many people stop opening them.
There can also be practical reasons some private messages go nowhere. Some people may limit who can message them, so your message might not reach them, or they may simply have closed the browser. People often come and go from random chat without logging out, so someone who looks available may already be gone. Don't send three follow-ups. If one specific message gets no reply, chatting in the room again is the better move.
Which questions get real replies instead of one-word answers?
The questions that get the best answers are specific, easy to answer and ask for an opinion. "Tell me about yourself" is hard to answer and feels like a job interview. "What's a food everyone loves that you can't stand?" takes five seconds to answer and almost always leads to an argument worth having. Either/or questions work well in group online chat because people pick a side: "Physical books or e-reader?" "Pineapple on pizza, final answer?"
In age-based rooms like the 40-plus or 50-plus chat, comparison questions get going quickly: "first gadget you owned that felt like the future?" Avoid anything that asks for personal details early on, such as exact location, workplace or surname. It makes people wary, and it goes against basic safety habits anyway. "What part of the country?" is enough. "What street?" is not.
How do I keep a chat going after the first few messages?
Stop asking only questions. A conversation that's all questions feels like a survey, and the other person starts replying with "yeah" and "idk." Answer your own question with a detail, then hand it back. "I can't stand coriander, it tastes like soap to me. You?" gives them two things to respond to instead of one.
In busy group rooms, start your reply with the other person's chat name. On mobile, people skim, and a reply without a name can look like it was meant for someone else, so the conversation quietly falls apart. When a chat does stall, don't fill the gap with "lol" or "so..." Bring up a different topic that's related to something they mentioned earlier. If they brought up their dog three messages ago, "wait, what breed is the dog?" will often revive a chat that looked finished.