Why did he unmatch me after getting my number?

Look at what happened before the unmatch. If the number swap came quickly and the chat was friendly but short, he may be someone who uses apps to collect contacts and then sorts them later. If the conversation cooled off right before he asked for your number, he might have been losing interest and used the number as a soft exit. If he was keen all the way through and went quiet after the swap, the unmatch could just be him clearing out tabs on his phone.

What she is signalling, or what he is signalling, shows up in the pattern rather than in one message. You can't read his mind, but you can see whether the texts you've exchanged matched the energy of the app chat. Be honest with yourself about that before deciding what to do next. If the texts were sparse or he never replied to your last message in the app, you were already on shaky ground.

The first kind is a light check-in that assumes he's just busy. It refers to something specific from the app chat, so he knows who you mean, and it asks a simple question he can answer in one word. Its job is to make a reply easy. It should contain no reference to the unmatch and no 'did I do something' tone. You can tell a draft is this kind because it's short and could be sent to anyone who had matched with you, but it still points to your conversation.

The second kind is a plain close. It says you enjoyed talking, that you're happy to keep it going if he is, and leaves the door open without chasing. This works when the first kind has already gone unanswered or when you suspect the app was the only thing holding the chat together. You know it's the right kind when it asks for nothing beyond a yes or no and has no question about the unmatch at all. Leave out apologies, explanations of your intentions, and any mention of how you feel.

Send your first text in the early part of the day, when people are generally checking their phones and less likely to be in the middle of a night out. Avoid sending anything after midnight, because a late message can read as either drunk or needy. Give him a couple of days before anything else. If you hear nothing, that's a clear answer for now.

If you send one message and get no reply, leave it. A second text, even a friendly one, usually turns a neutral silence into a decision not to respond. If he does reply later with a lukewarm message, you can respond once in kind and see whether he keeps the thread going. Once a week of silence has gone by with no reply, stop. You've done what you needed to, and continuing only makes it harder to move on.