Do people need to sign up to join a flash mob on Crowd?

No. Joining is one tap on the link. Crowd sets an anonymous cookie on the device to stop double-counting, and that's it. No email, no account, no app.

What if we don't hit the number?

The action expires at the deadline and is marked as ended. Nobody is committed to anything, and you can create a new one with a smaller target if you want another go.

Can I keep the location secret until the target is hit?

The description is public from the moment you share the link, so put the meeting point in it only if you're happy for it to be seen. A common trick is to name a general area and share the exact spot in your own channel once the action succeeds.

How far ahead should the deadline be?

For a flash mob, 24 to 72 hours works well. Long enough to spread, short enough that people don't forget. Crowd allows deadlines up to 30 days out.

Flash mobs

Organise a flash mob that only happens if enough people turn up

A flash mob with six people is just six people standing in a square. Crowd lets you set the number that makes it work, share one link, and only commit when that number is reached.

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The problem

The hard part of a flash mob isn't the idea, it's the guarantee. People will say "sounds fun" in a group chat and then not come, and nobody wants to be the one who turns up alone. So most flash mobs never leave the planning stage.

Why a threshold fixes it

You set the minimum, say 40 dancers. Below that the action quietly expires and nobody is embarrassed.
Joiners are anonymous and don't need an account, so the link can be dropped in a Discord, a subreddit or a WhatsApp group without friction.
The counter is live, so momentum is visible. People join because they can see it filling.
Time and place are on the page from the start. Once the target is hit, everyone already knows where to be.

Examples

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How to do it

1
Decide the number that makes the stunt land. Be honest: a freeze mob needs bodies, a choir needs a few strong voices.
2
Create the action with the place, the time and a deadline a day or two before.
3
Share the link where your people already are. Ask each joiner to pass it to one more person.
4
Watch the counter. If it fills, the page shows it reached and everyone shows up. If it doesn't, nothing happens and nobody looks silly.

Questions

Do people need to sign up to join a flash mob on Crowd?: No. Joining is one tap on the link. Crowd sets an anonymous cookie on the device to stop double-counting, and that's it. No email, no account, no app.
What if we don't hit the number?: The action expires at the deadline and is marked as ended. Nobody is committed to anything, and you can create a new one with a smaller target if you want another go.
Can I keep the location secret until the target is hit?: The description is public from the moment you share the link, so put the meeting point in it only if you're happy for it to be seen. A common trick is to name a general area and share the exact spot in your own channel once the action succeeds.
How far ahead should the deadline be?: For a flash mob, 24 to 72 hours works well. Long enough to spread, short enough that people don't forget. Crowd allows deadlines up to 30 days out.

Also used for

Ready to set a number?

One link. Anonymous. No accounts. If the number doesn't fill before the deadline, nothing happens and nobody is on the hook.

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