WhatsApp

Send messages, manage templates and contacts, run broadcasts and flows — one API for WhatsApp Cloud.

LazyApp is WhatsApp-only. Everything in these docs — sends, webhooks, templates, platform customers — sits on Meta’s WhatsApp Cloud API. You connect a WhatsApp Business Account (WABA) and phone number once; LazyApp holds credentials and gives you a stable REST surface.

Most teams start with quickstart, then read connecting WhatsApp when they need console or platform onboarding.

Quick reference

What	LazyApp
Message types	Text, template, image, video, audio, document, sticker, location, contacts, reaction, interactive
Template required	Yes — outside the 24-hour window
Upload limit	16 MB per file by default (MEDIA_MAX_SIZE_KB). Meta may refuse a type or size WhatsApp does not accept for that message kind
Scheduling	Yes — send_at on POST /v1/messages
Broadcasts	Yes — template campaigns with segments and caps
Inbox	Yes — Inbox guide, conversations API, and console
Group chats	Meta-gated — GET /v1/capabilities; see Group chats
Flows	Yes — Flows guide. Disabled on coexistence numbers
Calling	Meta-gated — check GET /v1/capabilities
Analytics API	No dedicated analytics endpoints

Do not hard-code calling, block lists, or India payments. Ask capabilities per connection — Meta can flip flags without a deploy on your side.

Before you start

WhatsApp requires a WhatsApp Business Account (WABA), not a personal WhatsApp account.

You need:

• A Meta Business Portfolio (business.facebook.com)
• A WABA (created during Embedded Signup)
• At least one phone number on that WABA
• Approved templates to start business-initiated conversations
• Awareness of the 24-hour rule — free-form replies only within 24 hours of the contact’s last message; outside that window you must use an approved template

New numbers often start in Meta’s sandbox tier (TIER_250 — about 250 unique contacts per 24 hours). The limit rises automatically as messaging history and quality improve. Watch messaging_limit_tier and quality_rating on capabilities and the phone_number.quality_changed webhook.

In this section

Sandbox

Test mode, claim a pool number, test recipients, webhook simulation

Connecting WhatsApp

Console Embedded Signup, platform setup links, coexistence, reconnect

Messages

Every send type, the 24-hour window, scheduling

Calling

Permission requests, call webhooks, and history — not a PSTN/SIP bridge.

Phone numbers

Connect your own number, monitor quality and limits, recover from disconnects.

Contacts & profile

Upsert contacts, record consent, business profile via Meta proxy.

Inbox

List conversations, fetch messages, reply with POST /v1/messages.

Group chats

Create groups and send with group_id — capability-gated; no participant APIs yet.

Templates

Create, submit for Meta review, sync status

Media

Upload, retention, Meta’s ~30-day expiry

Broadcasts

Template sends to a segment with quiet hours

Flows

Create, publish, send interactive forms — and collect submissions

Verify

OTP send and check with fraud controls

Webhooks

Signed delivery, retries, event catalogue

Capabilities

What each connected number supports today

Media & limits

Upload caps, tiers, analytics, and common Meta error codes

Build a platform

One workspace per customer, setup links, scoped keys

WhatsApp rates

Meta’s rates, billed to you by Meta. LazyApp adds 0%

Migrate from Kapso

Keep Meta-shaped sends on the proxy, move webhooks and setup links

Related endpoints

• POST /v1/messages — send any message type
• GET /v1/templates — list and manage templates
• GET /v1/contacts — contacts in the workspace
• GET /v1/conversations — conversation threads
• POST /v1/broadcasts — start a broadcast
• GET /v1/capabilities — per-number features and limits
• POST /v1/platform/setup-links — hosted connect for your customers

What we skip (Zernio-style)

Zernio surface	LazyApp
Buy a phone number via API	Connect your own number through Embedded Signup
Headless POST /connect/whatsapp/credentials	Console onboarding only — no public credentials-paste API
Conversation-centric inbox create	Recipient-centric POST /v1/messages
Sandbox sessions + reply activation	Test mode + console sandbox
Full groups API (participants, join requests)	Partial — create/list/send only; see Group chats
Click-to-WhatsApp conversion API	Not documented
Multi-network OAuth hub	WhatsApp only