Can unipath triggers watsapp message and collect the information for account creation, after which create the account in a 3rd web application?
Yes, it can.
You can set up a Business Account or Developer Account at Facebook Developer.
After you set up you WhatsApp for business account, you can make api calls to trigger messages or even set up a webhook to deal with incoming api calls and call the webhook’s end point from your UiPath project
Other options is use integration service or using a broker
For study purpose, I do something similarly to trigger UiPath’s automation from WhatsApp
Why facebook developer account is required?
Watsapp is part of meta group…and all the meta group applications have a common developer account to be created to use the respective api’s…it was referred as facebook developer account in the previous comment
Hope this clears