What’s the hardest part of integrating WhatsApp into your apps?

I’m building ZapClient, a simple API that lets developers send and receive WhatsApp messages using HTTP requests.

While working on this, I noticed that integrating WhatsApp into apps can be surprisingly complex.

Things like:

• Meta approval

• Templates

• Webhooks

• Scaling

• Automation

For developers here:

What has been the hardest part when trying to integrate WhatsApp into your product or workflow?

Would love to hear real experiences.