Messaging apps are a popular way for chatbots to communicate. They don't require creating a new Web page or application. The developers simply create conversational abilities and connect them to the app's API. Some messaging APIs provide additional developer aids, such as message templates and natural language processing.
Users give messaging apps some identifying information, if only a phone number. This gives participants a persistent identity for ongoing communication. Some apps let bots access the profiles of users that talk to them.
There are messaging apps for general-purpose conversation as well as ones with specialized purposes. Which apps are most popular varies from one country to another.
- Facebook Messenger lets chatbots connect to Facebook users. It has an extensive set of APIs to manage conversations and identify customers.
- WhatsApp belongs to Facebook but isn't closely tied to the platform. It appeals to users who want a high level of security. Facebook released a Business API for it in August 2018.
- Slack supports bots as Slack Apps with a conversational focus. The main focus of Slack is working teams, and a bot can help to support them.
- Telegram Messenger has a strong following in many countries. It has an HTTP-based API for bots. Bots on Telegram are visually distinct from human participants.
- WeChat is very popular in China and has followings in other countries. Weixin is a version of it which is available only to Chinese users. A developer kit is available for creating bots.
- Line is highly popular in Japan and other Asian and Indian Ocean nations. Its messaging API supports push and reply messages, user profile access, and group chats.
Each platform has its own terms of service, and chatbot project managers need to read them carefully before choosing an application. They may prohibit certain topics or unsolicited messages. Advance planning will avoid going down the wrong path.