Almost every business starts on the free WhatsApp Business app. It works well until it doesn’t: more customers, more people answering, and more messages that need to be tracked. At that point the WhatsApp Business Platform — usually just called the WhatsApp Business API — is the next step. This guide explains the real differences and how to decide.
The short comparison
| WhatsApp Business app | WhatsApp Business Platform (API) | |
|---|---|---|
| Cost | Free | Meta charges per template message by category; you may also pay for the software you use on top |
| Who answers | The phone plus a small number of linked devices | Any number of agents through a shared inbox |
| Automation | Greeting, away messages and quick replies | Chatbots, AI agents, workflows and integrations |
| Messaging customers first | Manual broadcasts to people who saved your number | Approved message templates, at scale |
| Integrations | None | CRM, catalogue, order and booking systems via API |
| Interface | The WhatsApp app | Software you choose, built on the API |
The 24-hour customer service window
The rule that shapes everything on the API: when a customer messages you, a 24-hour customer service window opens. Inside it you can reply freely. Outside it, you can only start a conversation with a message template that Meta has approved. Templates are categorised as marketing, utility or authentication, and that category decides how Meta charges for them.
Signs you have outgrown the app
- More than two or three people need to answer the same number.
- Messages get missed because nobody knows who is handling them.
- You copy enquiries from WhatsApp into a spreadsheet or CRM by hand.
- You want an assistant to answer common questions outside business hours.
- You need to send order updates, reminders or quotes to many customers.
Keeping the app: Coexistence
Historically, moving a number to the API meant giving up the app on that number. Meta’s Coexistence option changes that: the same number can stay active in the WhatsApp Business app on your phone while also being connected to the platform, so your team can use a shared inbox and automation without abandoning the app.
If you would rather move the number entirely, a number that is active on the app usually has to be removed from it before it can be registered on the API.
How to get on the API
- Have a Meta Business account (verification unlocks higher messaging limits).
- Choose the software you will use — it connects to Meta’s Cloud API for you.
- Connect your number through Meta’s signup window, or via Coexistence to keep the app.
- Create and submit your first message templates for approval.
LarkFlow supports all three routes — quick signup, Coexistence and your own Cloud API credentials. The WhatsApp setup guide walks through each one.
The verdict
Solo owner with a manageable number of chats? The app is fine. A team sharing a number, wanting automation, or needing WhatsApp connected to sales and support systems? Move to the API — and use Coexistence if you want to keep the app as well.