There are dozens of free bot building platforms these days which do not require any coding. I tried a few of them but after the Messenger allowed the bot usage on its platform, most bot-builders have changed their focus to Messenger only. Thus all development and support for other platform suffered.
Personally, I prefer Microsoft's QnA integration on their Bot Builder platform as it doesn't require any extra effort to deploy the bot on Messenger or Telegram or Skype or Slack or several other platforms. Earlier I was eagerly waiting for when whatsapp would give access to bots on its platform. But since I joined Steemit, I discontinued paying attention to these platforms as none of them supports Steem blockchain or Discord app. If you find any, I'd love to hear from you.
All the best for your experiments!
I am just getting into this, and chatfuel is my first attempt..thanks for the info.