Guestloop is live at guestloop.us.com. It does one thing: sends scheduled text messages to your event guests and shows you whether each one actually arrived.

The scope is narrow on purpose. Event details tend to die in a group chat half your guests have muted, or an email buried under newsletters. Texts are the channel people still read — they're just annoying to send at scale by hand, one pasted message at a time into 40 threads.

Create an event and it gets its own QR code and tap-to-text link. Put the QR code on your invitation, or drop the link in the group chat. A guest scans it, their messaging app opens with a pre-filled text, they hit send once, and they're on your list — no app, no account, nothing to fill out.

That one text is also the opt-in: Guestloop only ever messages guests who've texted in this way, and anyone can text STOP at any time to stop hearing from you.

From there you write messages and pick send times — a save-the-date, a reminder the week before, a parking note the morning of. Messages support variables like the guest's name, so one template goes out personalized to everyone. After each send, a per-guest delivery log shows who received it.

No subscription. Top up a prepaid balance of $10–$100 and pay 5¢ per outbound message — $10 covers roughly 200 texts. When the balance runs out, sends pause until you top up again.

It's web-only for now (it works fine in a phone browser; there's no app store listing yet). Messages go out from verified toll-free numbers with a clear sender line, and every message is screened, which occasionally means a legitimate message needs rewording. It's US-focused for the moment.

Roughly in order: a proper iOS app, email as a backup channel for guests who don't do texts, and team accounts for planners managing events on behalf of clients.