How do you do that? How do you get someone's email from a text she sent?

When I tested it the text was "Thanks! You can reach me at ##########. Could you please reply with your email so we can add it to our list?"

http://arshadchowdhury.com/740-how-i-built-a-business-in-a-w...

Personally I would much prefer writing over texting a random number (with a follow-up text for my email), but I guess an advantage is that it avoids queues at the sign-in sheet.

I can see some applications, and knowing the cost of the administrative portion of promotions, making it easier to be an expert at it definitely has monetary value.

I feel like there's a fantastic use case for the parent's project; I'm not quite sure what it is yet.

Where are you getting the email addresses from?

"Thanks! You can reach me at [my number]. Could you please reply with your email so we can add it to our list?"

I can see the benefits of the pitch that people only need to text the codeword but you could presumably extend the service to offer greater parsing of message content e.g. people can text the codeword, name and email and you parse them out rather than ask people to reply again with their email address.

typo: Dogpatch Labs by no means normal. It’s a small, tight community of tech entrepreneurs who love to help eachother

"eachother" should be two words

I doubt it: Everything was done within 30 square feet

A bit picky here, but you may as well get it right: 30 square feet is a tiny area for a workspace: for example, a room (closet, really) measuring 5ft by 6ft would have an area of 30 square feet. I doubt that's what you meant. You probably meant that everybody was within 30 ft of everybody else, or something of this nature.

I can certainly see the benefits for conference organisers. I also think it might be popular for restaurants/bars who normally obtain business cards (to add to mailing list) for entry into monthly prize draws.

How are you obtaining a person's email address from a text message?

Now that you wrote an article on it, there will be other people that will build a similar business in a weekend and compete with you.

He should build his advantage on being the first and having a better product. Techical services he's using are not part of his core product.

..as tons of other startups do, and actually the only external services they use are Twilio and Stripe, others cited are just opensource frameworks/technologies (RoR, Bootstrap).

..and they are disposable. Most startups I see I know won't be around in 2 years.

they won't be around not because of the external services they've used but because they wont find the right business model. It's like saying that every ecommerce around will fail because they're using and external payment processor like Paypal. Maybe some of them can fail because of a Paypal "horror story" (account blocked etc..) but most of them will fail because they are not profitable.

I partially agree with you that relying on external services could be a risk, but in this case they've chosen services for some part that are not so easy to implement internally, and for that they've picked two new but highly growing services.

There already were competitors: http://presentnow.me

I'm going to have to disagree with you there. Neither Twilio nor Stripe are in the same business line as RollCallMe and thus are offering services, and thus not competing, therefore they have an incentive to keep prices down in order to attract more customers. I cannot speak for Stripe, but Twilio has lowered their rates in the past and does a wonderful job in regards to both technology and customer service.

Yes, there are no technical barriers to entry into this one-service industry, aside from knowing a Rails person who can wire up the app, but time-to-market, initial pricing and the potential for add-ons that can engage more users and augment the revenue streams give them the advantage. Choosing Twilio gives them that advantage.

Not a rock-solid app by any means, but one that's needed and doesn't compete directly against more mature and properly funded platforms.

Great idea. I wish them good luck.