Coronavirus: Create A Phone Number Which Plays Podcasts or Sermon Recordings Over the Phone

With many people going into self-isolation for weeks or possibly even months at a time, we’re seeing a huge surge in use of video calling and video conferencing services as a means for people to both stay in touch with friends and family as well as working from home.

However, for some members of society including the elderly and most vulnerable, these high-tech solutions may not work because they rely on having Internet access, a decent computer/laptop/tablet/smartphone and a certain degree of knowledge and experience to be comfortable using it.

With yesterday’s announcement that all Sunday services at Churches around the country are to be stopped until further notice, we have – at my church – already started planning to produce a short video to be published on Facebook, YouTube etc. on Sunday mornings, as well as the usual sermon recording/podcast which I already produce each week. With the restrictions now in place, the weekly podcast will be more important than ever but it does, of course, rely on an Internet connection and a device such as computer, smartphone or smart speaker to listen.

How to Build A Telephone Number For Podcast Listening

To get round this problem and make the audio recordings as accessible as possible for everyone, I have built a simple app using Twilio, which is a cloud communications platform that lets you build telecoms apps in the cloud which can do all sorts of things. Don’t let that scare or overwhelm you; what we’re going to be building is very simple and easy to set up.

Video Tutorial Also Available!

If you’d prefer to watch me demonstrate this in a video rather than follow the written guide below, you can watch the YouTube video instead. Then, please give it a thumbs-up, subscribe to the channel and leave a comment – thank you!

Step 1: Sign up for a Twilio Account

Sign up using this link: http://www.twilio.com/referral/cTXU0Q for a free trial – it’ll give you and my church $10 free account credit, too – which will help us both out 🙂 [You don’t need to spend any money until it’s up and running and working… more on that later on.]

You’ll have to verify your Email address and a mobile phone number as part of this process.

Step 2: Set Up Your Account & Get a Phone Number

Once that’s done, you’ll see a wizard which asks you some basic questions to get started, the first of which is “Do you write code?”. You can say no to that if you don’t, and then select “Build something on Twilio myself“.

You’ll then be taken to your project Dashboard where you’ll see that you have a Trial Balance of credit to allow you to test and build your app. The first thing you’ll want to do is to click on Settings and give your project a name, like Dial-a-Sermon. Scroll to the bottom and click Save.

Then click back on your Dashboard and click the red “Get a Trial Number” button. You’ll be given a United States phone number to begin with, but if you’re elsewhere in the world and want folk to have a local number to call, click where it says “Don’t like this number?”

I’m based in Liverpool where the area code is 0151, so getting a phone number with a local area code with which people are familiar is probably a good idea. Select “Voice” under capabilities and then type the area code minus the leading 0 (if you want) in the Number box and press Search.

This will bring up a list of phone numbers that you can choose from, so pick one with a nice easy-to-remember sequence of digits, if possible, and click Buy. As you can see, the cost is $1 per month or just a smidgen over 75p in Great British Pounds. It’s not free, but it’s very low cost!

(Note – it actually is free until you upgrade your account to let people start using it.)

On the next screen you’ll confirm and then press Buy again. If you’ve not already added your address to your account, you’ll need to do that as one of the purchasing screens asks you which address on your account you want to associate the new number with. If there’s no address on your account, you can add one at that point.

Step 3: Write a Function to Play an MP3 File Down the Phone to Callers

Now you’ve got a number, you need to tell Twilio what you want to happen when people call it. Click the three dots to open the menu up for your Project and click on Functions, which is right down the bottom of the list under RUNTIME:

Click the red “Create a Function” button and then select the template called “Hello Voice” and click Create:

By default, this creates a function called Hello Voice which when called will play a synthesized voice which reads out whatever text you choose. In the initial example, it will say “Hello World” to the caller. You can change this to instead play any publicly available MP3 file.

If you already run a podcast for your church or other organisation, you’ll just need the full, public URL of the MP3 file you want to play (you can test it will definitely work by pasting it into your web browser’s address bar). If you host MP3 files directly on your website you can also use the full URL from there, or you could also host in something like Dropbox or Google Drive and make it publicly accessible.

Delete everything in the code section and instead paste in this slightly different code:

exports.handler = function(context, event, callback) {
	let twiml = new Twilio.twiml.VoiceResponse();
	twiml.say("Welcome to Saint Anne's. This week's sermon will start shortly, please wait a moment.");
	twiml.play("https://sermons.stannesaigburth.com/08Mar2020.mp3");
	twiml.hangup();
	callback(null, twiml);
};

The code first reads out any message you like, then plays an MP3 file (Line 4) and then I’m sure you can guess what Line 5 does! Reading out a short message at the start (Line 3) is optional, and you can remove that line altogether if you like, but it will play immediately and gives callers positive confirmation that they’ve got through to the right place, which can help as there’s sometimes a short delay whilst the MP3 is loaded before it starts playing.

On the fourth line, you’ll have to replace that URL with the URL of your own MP3, obviously. Be careful to keep the single quotes inside the brackets around the address, or it won’t work.

Note: you must make sure that the MP3 is publicly visible if you’re hosting it somewhere like Dropbox or Google Drive.

Dropbox Method:

For Dropbox to work you need to add the following to the end of the file’s public URL:

&raw=1&t=.mp3

This is in addition to the “?dl=0” that you should already have at the end of your Dropbox URL. Therefore, your complete Dropbox URL should look something like this:

https://www.dropbox.com/s/xxxxxxxxxx/sermon.mp3?dl=0&raw=1&t=.mp3

Google Drive Method:

For Google Drive, it’s slightly more complicated than just adding something to the end of the URL, like with Dropbox. However, it’s still easily done.

First, get your shareable public URL from Google Drive, which will look something like this:

https://drive.google.com/file/d/*****/view

The ***** above will correspond to the unique ID of your file – select JUST that ID (so between the /d/ and the /view portion of the URL) and combine it with the following new URL:

https://docs.google.com/uc?export=download&id=

Once you’ve done that, you’ll have a URL which looks a bit like this:

https://docs.google.com/uc?export=download&id=*****

(Again, the ***** above represents your file’s unique ID.)

Take that URL and paste it into the function code in your Twilio function, between the single quotes.

Moving on…

Next, enter a path (like /sermon) in the properties field above, and give the function a name you’ll recognise, like “Play latest sermon recording”. Once you’ve done that, you can press Save and your function will “deploy”!

Step 4: Configure your Phone Number to Run the Function from Step 3

Click the three dots on the left column again to bring up the menu, and select “Programmable voice”. This is where we will program your voice number to execute the function we’ve just written. Don’t worry – it’s literally just selecting the function from a drop-down menu!

Click the “Numbers” item in the submenu for Programmable Voice and then on the Phone Numbers screen click Manage Numbers.

You’ll see a list of all the phone numbers on your account (there’ll only be one) and as you can see, it’s currently configured to play a Twilio welcome message.

Click on the number itself to bring up its settings, and then scroll down to Voice & Fax.

Under the option entitled “A Call Comes In”, select the dropdown and change it from Webhook to Function. Then next to it, select your function (which we made in the previous step) from the list and then press Save down at the bottom of the page.

Step 5: Dial A Phone Number to Listen to Your Podcast!

If you now call that number, you should hear the following message:

You have a trial account. You can remove this message at any time by upgrading your account. Press any key to execute your code.

Twilio / How to Create a Phone Number to Call and Listen to Podcasts or Other Audio

Press any key and voilà! The MP3 file which you specified in the code above should start playing down the phone!

Note that if you’re still on a trial account and haven’t yet upgraded, the call length is limited to 10 minutes. This is so that you can test your app properly before launch, but stops people misusing the trial accounts for production projects!

Updating your Phone Number to Play Most Recent Podcast or Audio Recording

Each week, or whenever you want to change what audio file the phone number plays, just login to your Twilio account and edit the function with the URL of the new audio file to be played.

If you’re comfortable with code and want to expand this further to automatically grab the latest MP3 from your website or podcast’s RSS feed, Nick Holcombe has expanded upon my basic solution for any seasoned coders out there. You can see his post here: https://www.brightec.co.uk/blog/podcasting-to-those-without-internet-access

Now, Upgrade Your Account

To get rid of the demo message and 10 minute time limit and start using the app, you’ll just need to upgrade your account with some billing details. For me, that just meant topping up £20 which should last a good long while as the phone number costs just ~75p per month to keep and incoming calls to the number cost you, the operator of the number, only $0.01USD a minute which is about 0.84p!

A Note on Call Costs…

A few people have asked this so I thought it would be worth clarifying: If you choose a local, geographic phone number (eg. 0151 for Liverpool, 0121 for Birmingham, 020 for London etc.) then this will cost the person dialing the number exactly the same as what it would cost them to dial any other similar number. In other words, there’s no extra charge whatsoever. If they have “free minutes”, it will be included in those – so to all intents and purposes, for the majority of people, it will be free to call. You just need to keep your Twilio account topped up with credit to receive the calls. (see above)

In Conclusion…

I hope you’ve found this tutorial useful during this strange time of extra need, and I hope many elderly and more vulnerable people will really benefit and feel less cut off from the outside world and their church communities as a result of this.

If you build this, please let me know as I’d love to see how far and wide this gets used. Comment below or tweet me @paulfp.

And of course, if you have any problems – I’ll be happy to help as much as I can.

Best wishes and stay healthy.

Update, 1st May 2020: Comments Now Closed

Comments on this article are now closed, however I’m still very happy to help and advise anyone wanting to set this up! To ask me a question, please follow me on Twitter and then tweet me your question – I’ll respond as quickly as I can!

You can also watch the video version of this tutorial and comment on the YouTube video for help.

Join Our Facebook Group!

If you’d like a place to discuss this topic and expansions/extra development, I’d also encourage you to join the Switched on Network Facebook group: https://www.facebook.com/groups/SwitchedOnNetwork/