Commercial Products
Dec '08

A Basic Voicemail System using Twilio

posted by delano

We setup a voicemail system this week using Twilio. There are other similar services but Twilio was the first one we've found that's both available (CloudVox is in private beta) and really simple to get started.

If you aren't familiar with it, Twilio is a voice communication system with an HTTP/XML API. You create an account with them and they give you a phone number and an API key. Then you write some code that outputs XML (they have libraries for Ruby, Java, Python, and PHP and configure your account to point to an XML resource to handle the initial incoming call. They charge $0.03 or $0.05 cents per minute depending on whether you're using a local or toll free number.

We've posted one of our test configurations to Gist (we blame the PHP on the intern :p sorry Dave). Here's our initial feedback:

  • The XML is based on simple verbs (Play, Say, Record...) so it's easy to get started. I've read complaints about using XML in this way, usually on the basis that it's over simplified and proprietary, but I disagree. If something can be simplified, simplify it. And if it's easy to work with, the fact that it's a proprietary language doesn't matter. (On a side note, is there a standard, open language for controlling voice communication systems?)
  • The debugger is pretty cool. You can look at the recent requests and responses between their system and your web service. We solved two problems like this (XML encoding issues, again).
  • The mp3s don't play properly in Safari (we're running 3.2.1). It displays a black screen that says "No video". Sometimes it will play after you hit the spacebar, sometimes not. Firefox is fine. Update: this looks like it could be related to Flip4Mac, which I updated last week. The same thing is happening with other mp3s.
  • I somewhat concerned about jerks calling in many times or for long durations to charge up our bill. This is an issue with all similar services but I didn't see anything in the docs or API that would prevent this in Twilio.
  • The prices are reasonable for moderate use but I expect they should decrease as their customer base increases (they should be able to negotiate lower rates from their suppliers).
  • Their customer service is excellent! We experienced it and so did our friends at Dealer Diagnostics.

We'll be looking at other options and we'll post our findings here.

I'm Delano Mandelbaum, the founder of Solutious Inc. I've worked for companies large and small and now I'm putting everything I've learned into building great tools. I recently launched a monitoring service called Stella.

You can also find me on:

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Solutious is a software company based in Montréal. We build testing and development tools that are both powerful and pleasant to use. All of our software is on GitHub.

This is our blog about performance, development, and getting stuff done.

-       Solutious