I wasn't worried about paying them too much for Appointment Reminder, but I certainly won't refuse getting a few hundred bucks knocked off my expense projections.

Now if I can only get to paying them $10k a month to get the bulk rate... crosses fingers

why not just colocate your own asterisk box?

For the same reason I don't write an optimized BingoMongrel in C to lower my memory footprint and save $25 a month on my hosting bill: a) that introduces technical risk into a project which doesn't need it at all and b) the cost savings are swamped by the investment in engineering time.

Plus, four weeks spent teaching myself Asterix is four weeks I can't spend doing things like coding the part of the app people actually pay for or doing consulting, which could buy me a X * 10^7 minutes of call time or Y months of salary in the bank for employee #1.

You left out (c) Facilitating Mark Dowd's awesome Bingo code injection exploits.

Wasn't memory allocation errors, stack overflows, and code injection implied sufficiently by the words "in C"?

This is nice to hear. I am currently putting something together using Twilio to make it super simple to get local or tool free numbers to use as tracking numbers for print, web and SEM. The numbers forward on to whatever normal business number you would use, but the call information is all tracked and logged. It can also ping Google Analytics for you or ping your own custom page on your server. This way you can know exactly how many calls resulted from a print campaign, or from your website, etc.

I was interested in implementing something similar for a web directory that would enable tracking offline phone conversions via Twilio. I was going to use click-to-call, however, click-to-call requires paying for both the inbound and outbound portion of the call. Is there a way to have one inbound number forward to a different number dynamically (depending on a phone number variable)?

Yes. Every request we make to you includes the 'From' number, which you can check for in your code, and return a <Dial> with the number you want to forward them to specified. http://www.twilio.com/docs/api/2010-04-01/twiml/dial

Sounds interesting. Are any outbound minutes used after the call is forwarded? I am willing to budget for the inbound connection and tracking, but paying for the entire outbound conversation would be a bit too variable.

Twilio is not currently able to hand off a call to another carrier, so you have to pay for the outbound minutes when you call out with <Dial> or the REST API to connect another party

Just in case you are not aware of the following: Twilio can't fully handover forwarded calls to another carrier; therefore, you will be charged for the length of the call rahter than for the time it takes to reroute the call to another carrier.

Yeah I'm aware of that and plan on working a metered usage for minutes into my app.

I've previously setup Elastix (Asterisk/FreePBX distro) on a VPS for another business - price was right on the DIDs and minutes, but making it work nicely on VPS, learning Asterisk+FreePBX quirks, and keeping everything up to date quickly became a time-waster.

Twilio/OpenVBX looks like it might be a comparative breeze to setup and use - and let us focus on our core competencies rather than burn time becoming Asterisk/VOIP gurus - but the fact that they aren't built on open standards like SIP makes me a bit nervous. Anyone have any experience with OpenVBX, thoughts, alternatives I'm missing?

Edit: Twilio has somewhat confusing statements inre: Canadian toll-free numbers at http://www.twilio.com/faq/international. Anyone know if they provide US toll-free numbers that accept calls originating from both the US and Canada?

Hi, I work at Twilio and wrote that FAQ. Clarification; Canadian customers can definitely get toll-free numbers that US and Canadian users can call. However, Canadian callers often will get misreported in caller ID, which is a deal-breaker for many use-cases. But these numbers are available and functioning for Canadian customers.

Also, our US toll-free numbers accept calls from US and Canada.

Thanks to both of you. Munged caller ID is definitely not a deal-breaker for me.

I can really see Twilio becoming a blockbuster startup.

I think we'll see several multi-million dollar companies built on Twilio. It makes every phone into a smartphone (i.e. a first-class citizen of the Internet which speaks HTTP). That is just gobsmackingly awesome if you have a good way to exploit it.

We (I work at Twilio) also announced a new developer contest today. The winner will be flown to NYC to meet with Fred Wilson, Albert Wenger and Brad Burnham from USV: http://contests.twilio.com/

I emailed you guys about a terms of use question but never heard back. I'd love to know if your "no unsolicited calls" line would apply to non-profits and political organizations. Call through voter lists where it is legal under current law. I got an app ready, but am hesitant to market it if it is going against Twilio terms of service.

Can you email me directly [email protected] and I'll find your request and follow up with it ASAP?

Sent.. thanks..

Can someone explain what "inbound call" and "outbound call" mean in this context? Do they mean the "up" and "down" duplex components of a single call, i.e. it's now cheaper if you only listen when people call in and don't say anything back?

An inbound call is when someone calls your application. An outbound call is when your application calls someone.

Thanks; that's what I originally thought, but something about the wording of this article confused me. Outbound calls that result from inbound calls? I guess this just reflects the way a lot of applications tend to use Twilio's service.

Yeah, that's really one of the refreshing things about what Twilio has to offer - they've gone through pains to simplify all parts of the process. The pricing is straightforward, the API is easy to use, and they have gotten really good at community response. It really sets them apart from most of the other Asterix service providers around.

Wow, thanks -- awesome quote, you can write our press release anytime ;)

Yeah, I also didn't understand if they meant outbound legs or outbound calls.

If I follow correctly.. it may be more expensive in some cases.

Their email states the outbound <Dial> is 2cents a minute.

Take the case of an minute long inbound call that uses <Dial> for two short outbound <1 min calls.

How much does that call cost? Previous it was 3cents, does it now cost 1 cent, or do those outbound calls now add to the price making it a 5cent call? (1 in + 2*2out)

It would be 1c/min for the duration of the call, and 2c/min for the duration of each dial.

If they split it up, they didn't split it up so you could combine the calls arbitrarily again. So, I'm leaning toward the latter. But, I don't work there so maybe someone else will have a better answer.

I tried to explain the various use cases and call legs in our blog post: http://blog.twilio.com/2010/09/announcing-new-pricing-for-th...

let me know if this helps, if not I'll work on a better explanation

That explains it. So price raise in my case. Doh.. no worries. You guys are worth it.

Cool, though I probably would have paid double :)

aww thanks Daryn :) Instead, how about using 2x as much?

He's going to have to use it four times as much since it's now half the price :).

haha or maybe even more, some use cases are 66% cheaper. darn precision, i was just trying to make it sound cheeky

For any Twilio staff reading.... any plans to get UK SMS working at a reasonable price point? I signed up a good while back but it wasn't working at the time.

We hear ya loud and clear! SMS outside the US is tough to get complete coverage of, since carriers vary so widely, but it's definitely one of our top requests.

If they want more users, why not expand internationally, instead of (just) slashing prices?

You can make outbound calls internationally but it's very expensive to call a mobile outside of US/Canada.

How many of their customers could afford to run their service when it costs so much to make a mobile phone call internationally (i.e. $0.32 - $0.493 for the UK)? Compare that to $0.02 for US/Canada.

Yeah, I can't wait for the international offering to be enhanced. I'm in the UK and have done some development using Twilio, but find that the end results are just a little bit too inconsistent - especially with SMS it seems.

While really nice, this is more fine-grained pricing and not so much "slashing prices". Anyone that takes incoming calls and then makes a subsequent outgoing segment or anyone that sends/receives SMSs will pay the same as before.

That's true. But a significant portion of our customers will see savings of 33-67% for their use cases. Single-leg is more popular than I think people realize.

Yeah, I should have mentioned that for many use cases, this would effectively be a price decrease. I was just expecting a drop for SMS when I first read the headline.

Nuts, doesn't look like that'll benefit me, I just use SMS sending.

Same here, I was hoping to see a cut in SMS pricing or at least the opportunity for volume pricing.

If you're just sending SMS, why not use one of the abundant tier 1 providers (http://www.usshortcodes.com/csc_aggregators.html) and pay bulk rates? I think we get something around 1c per outgoing, and 1/3c per incoming.

Awesome. Does Twilio support MMS? If not, when will it?

Nope, we don't support MMS but it is a popular feature request. No timeline on if/when it will be offered though

Danielle,

Any plans for Twilio start accepting non-US costumers?

Thanks!

Anyone up for sharing their Twilio projects? I've always been interested in the platform, but I've seen relatively few applications built on it.

I built http://phonetapapp.com during DjangoDash a few weeks ago using the Twilio API. The whole thing is available on GitHub as well. http://github.com/bnmrrs/PhoneTap

awesome, I'd love to feature this on our blog. Please email me at [email protected] if you're interested, and we can brainstorm the story

Done! http://blog.twilio.com/2010/08/ben-morris-wins-twiliomongodb...

We just launched a new gallery full of applications built with Twilio: http://www.twilio.com/gallery We also write about how people are using it one or more times a week on the blog: http://blog.twilio.com. We go to great lengths to promote our customers. We spend as much, if not more, effort on promoting our customer's projects and businesses as we do promoting ourselves.

Still pretty expensive for out-of-US destinations.

Just checked, it's still 32c per minute to call the UK.

When will there be a UK operation?

That's only for some mobile numbers. Landlines in the UK are currently $.03/minute. We're working on adding more international capabilities soon. Stay tuned.

Aside from businesses, I don't know anyone with a landline :)