Anyone who has ever tried to make plans with a big group of people – especially when they’re scattered throughout an event as huge as SXSW – knows it can be tough. But, luckily, that’s where GroupMe comes in.

The free app, which works on iOS, BlackBerry, and Android, allows you to assign contacts to specific groups (for example, "family," "roommates," or "SXSW friends") so you can ping them all at once and quickly. When you want to start a conversation on a particular topic, but aren’t sure who’s interested, you can start an Open Group for others to join.

Private conversations are still possible with the app, and the GroupMe team said it’s just like free texting. You can "send all the messages you want, and you’ll next pay a cent."