Two-way SMS, WhatsApp and email — in one thread

A lot of South Asian wedding logistics happens on WhatsApp. Aunties run the mehndi planning in a group chat. Cousins coordinate the sangeet routines on broadcast lists. Your dad forwards baraat-band quotes the same way he forwards every chain-message — over WhatsApp. SMS is a fallback for the older US relatives; email is for the work crowd; WhatsApp is the default. Anvaya treats it as the default too, not as an afterthought.

WhatsApp Business API is wired in through Twilio with delivery status and reply capture in the same guest timeline. Send a ceremony update or an RSVP reminder over WhatsApp natively — not by email with a "share to WhatsApp" button bolted on. This is the channel gap that matters most when the family conversation has already moved out of email and into threads guests actually check.

The same guest texts you on Monday, WhatsApps Aunty on Tuesday, and forwards the work-crowd RSVP from Gmail on Thursday. Generic wedding-tech tools see three different identities. Anvaya sees one guest. Phone numbers are normalised to E.164 so the SMS short-code from a US number and the WhatsApp message from the same number resolve to the same record. Inbound email-forwards are matched on the from-address; ambiguous matches surface for one-click confirmation rather than silently fragmenting the thread.

The dashboard renders the timeline channel-agnostic. You see a WhatsApp bubble (green), an SMS bubble (blue), an email bubble (purple) in chronological order, each with sender name, timestamp, and delivery state. When the guest's number changes mid-planning — a UK guest swaps their carrier, a Canadian relative moves — you merge the records and the history follows. When you reply, you pick the channel inline: reply on the channel she used last, or push a new send out over WhatsApp regardless of where the inbound came from. The composer remembers the per-guest channel preference and defaults to it next time.

Sending an RSVP reminder is only half the work. Knowing whether it landed and whether the guest replied is the other half. Anvaya shows delivery state for every outbound: pending, sent, delivered, failed, and replied. WhatsApp and SMS status callbacks update the dashboard as providers report delivery state. Failed or bounced numbers are flagged so you can fix them before the reminder window closes — no more sending the same SMS to a dead number for six weeks.

The reminder cadence is segmented automatically. The composer shows you which guests have not yet answered the haldi, which have already received the previous reminder, and which have replied but with a maybe. You send only to the guests who need it — three to seven days before the deadline, with a final pulse forty-eight hours out. Anvaya tracks per-guest send history so you do not double-text the guest who already replied yes yesterday over WhatsApp. The result is a reminder that actually gets replies, not a guilt-trip-broadcast that burns your sender reputation.

Anvaya runs on Twilio's carrier-grade infrastructure — the standard for transactional messaging. Outbound SMS, WhatsApp, and email all flow through a single send pipeline that handles retries, sender rotation, and rate-limit back-pressure. Phone numbers are normalized to E.164 on entry so a US 415 number, a UK 07 number, and an Indian 91 number all match cleanly between the guest record and the inbound webhook.

Inbound SMS and WhatsApp webhooks are signature-verified at the edge — every payload is checked against the Twilio auth token before it touches your data. Status callbacks (sent, delivered, failed) update the per-message delivery state in near real-time. Email-forward inbound is a separate path: a guest forwards a reply from Gmail, the email worker parses the message, signs the payload with an HMAC shared secret, and posts to the main app for guest-matching. International numbers are normalized before sending, so a UK, Canada, India, or UAE guest can stay attached to the same record and message history.