LINE Official Account can send various types of messages to users via two main messaging methods, reply messages and push messages:
Reply messages (Replies)
Reply messages are sent in response to user actions, such as LINE user is adding your LINE Official Account as a friend or initiating a message to your LINE Official Account. You have up to 1 minute to send a reply message without charge. Any subsequent messages after the first reply message or more than 1 min since the user's last user actions will be push messages.
There are several types of push messages:
Push messages (one-to-one)
Multicast messages (one-to-many, targeting a list of user IDs)
Narrowcast messages (one-to-many, targeting a segmented list)
Broadcast messages (one-to-many, targeting all friends)
Only push messages (one-to-one) are supported by the Conversation API.
You can send a push message under one of the following conditions:
Users who have added your LINE Official Account as a friend
Users who have sent a message to your LINE Official Account within 7 days in the one-to-one chat.
The Sinch Developer Documentation site contains comprehensive documentation and tutorials, which show you how we support LINE through the Sinch Conversation API.