Quite recently, we've figured out that we can improve our internal flow in terms of answering clients' calls, coming primarily from abroad. The idea was to build a simple app that will intercept incoming calls, post a Slack notification and allow us to answer these calls through a web browser using Twilio number. That’s how Callio was born. In this article, you will find a comprehensive guide on how it works and how to integrate it with your account.
No need to have an actual phone in your office – you just need a web browser, no additional devices.
No problems with clients who can't reach your number – owing to Twilio you can pick a number from dozens of countries.
Anyone on the Slack channel can answer the call.
Callio retains a full history of your phone calls along with a recording of each one. If you miss something, you will still have a note on Slack that somebody was trying to reach you
How Callio Works in Practice
Someone calls you.
Callio posts a notification on your Slack channel with a link to the web browser where you can answer the call.
You click on the link in the notification.
When you click on the ‘call’ button in your browser, another notification is posted on Slack to let the rest of the team know that somebody has already answered the call.
A call is performed and recorded.
When one of the parties hangs up, Slack issues a notification about that, and the line is ready to use again.
The call details and the recording are added to the call history
How to Set Up Callio
To start using Callio you have to sign up to Twilio and pick up a number you want to use. It's free and provides full functionality for testing purposes – you will only receive a short message advising that you're running a trial account.
Twilio incoming connection webhook
After registering on Twilio and choosing a number, you have to configure your first webhook. To do this, paste the address of your Callio app under Phone numbers, then: Configure -> Voice -> A CALL COMES IN
Twilio webhook for finished connection
In the same place that you paste the Callio incoming call webhook, you can type in the address of the endpoint for notifying users that the call has finished. It's under the ‘CALL STATUS CHANGES’ input field (see screenshot above).
When you're done with the number, go to Programmable voice -> Tools -> TwiML apps and create an application. Your Twilio app will be ready within a few seconds (you’ll need its SID later). Next, you can configure a webhook to handle voice calls by simply typing the address of your Callio into Voice's requested URL.
When we're done with Twilio, it's time to create a simple Slack application. Go to https://api.slack.com/apps and create an app. You'll need its token as well. Remember to setup proper permissions for this app to be able to post messages on your channel. The only permission we need is chat:write:bot.
You have to provide some secret data in the config.yml file. A sample config file should look similar to this:
Slack client token: it's a token that authorises your Slack account when you use the application. First of all, you have to create a Slack application (just give it a name and permissions as above), and you'll get the token when you choose your app under https://api.slack.com/apps.
Slack channel: it's just the channel name where you want notifications to be posted. It can be anything, as long as the channel actually exists.