To publish your Gupshup chatbot to Viber Public Account(PA), you will first need a Viber Bot Account. Click here to apply for a Viber Bot Account.
Once your application has been approved, Viber will send you a message inviting you to create a bot.
Follow the URL to create Public Account.
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Once you are done with Public Account details, you will be asked to choose chat solution. Select 'Viber Chat API' to get your app key. Keep a note of this app key.
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By now your Public Account(PA) is setup and you have your PA name (which in this example is 'TechNews') and the App key. Let us submit these details to Gupshup platform to link your Gupshup bot with your PA.
Go the Gupshup Bot Builder's Publish feature,
Choose Viber
Paste the app key as well as the name of your Public Account. Hit Submit to take your bot live.
You can now look for your chatbot on Viber Public Account
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Here's a video that details the entire process: