I think there's plenty of options but the issue is actually getting your friends/players to engage with yet another app.
- Google Calendar can invite groups (Contacts -> Labels) but that does rely on your players to read and acknowledge emails. That's getting harder lately, I think. Old people never did it. Elder Millenials getting tired of email after using it for work and social for 25 years. Younger Millenials barely adopted it, Zoomers never did.
- A meetup.com group could do it, and a free account can probably get you what you want. Free meetup groups are limited to like 10 attendees per event, but maybe that's perfect. But, again relies on your users installing an app or paying attention to emails.
- A facebook group might be the most realistic "free" way to plug in to people, but that gives me heartburn, personally, I deleted mine years ago.
- IDK about you but in my group of actual friends, a Discord server is probably the way to go. They all have the app and monitor messages. I don't know how well that will work for pulling in new players.
