Having the ability to send SMS Alerts to your users can be very effective in getting them to keep coming back to your .mobi site regularly, but it can be costly.

The Problem

I've been struggling to find a cost-effective way of sending SMS Alerts to users of one of my .mobi sites I'm currently developing. The cheapest bulk SMS Gateway provider I could find charges more than $0.05 per SMS sent. Now that may sound cheap compared to what we are accustomed to paying for sending text messages from our mobile phones, but if you have a site with 100,000 users and you send, on average, one SMS Alert per user per day, you'd be spending 100,000 x $0.05 = $5,000 a day, or $150,000 a month just to provide simple SMS Alerts to your users.

I was thinking, there's gotta be a cheaper way. Well, after some research online, I've discovered a completely FREE (for the sender) way to send SMS Alerts to your users. This might not be the best free method available (if you know a better one, please do share), but it works (just tested it with my brother in Canada) so I wanted to share it immediately with you guys who might be looking for something similar.

The Solution

It's called E-mail-to-SMS. The worst part is that I played around with this feature a few years ago for something completely unrelated to mobile websites, but it didn't click that I could use this as a completely free way of sending SMS Alerts to users until now. The way it works is simple, several operators allocate an e-mail address usually in the form of phonenumber@operatorsdomain.com, and if an e-mail is sent to that e-mail address, the operator automatically forwards it to the user as an SMS. Since it doesn't cost anything to send e-mail, it doesn't cost the sender a penny. (However, some operators charge their users to receive such SMS messages, but that's out of your hands. ) You just program your server to automatically shoot out an E-mail-to-SMS whenever a specific event happens (e.g. the user has received a new message), and the user will be immediately notified of the event, making them run to your mobile site to see what's up. That's how you keep them coming back for more! (Of course, you should give them the option to disable this feature).

The Downsides

There are only 2 downsides to this method that I've uncovered so far. First, not all operators have this feature, but enough of them do to make this a much more cost-effective way of sending your users SMS alerts (perhaps if there's an increase in the use of this feature, more Operators will enable it, in the meantime, you can tell users whose operators don't support this feature to use Teleflip.com). Second, you need to know what Operator the user is on, which is made especially difficult now that number portability is widely available. However, you can remedy this by either asking the user what operator they are on when you ask for their mobile number during registration, or you can simply send their number to each operators e-mail domain, knowing one of them should work (I know, crude, but it would theoretically work).

Here's a full list of compatible operators and the format of their E-mail-to-SMS addresses:

Until I find a better way of sending free SMS Alerts to my users, it's going to be my method of choice. I can't do without this feature on at least one of the sites I'm currently working on, and the thought of paying 6-figures for it made it unfeasible, so I felt like I had discovered an absolute goldmine when I found this free alternative (I was so excited I even created a new SMS sub-forum here! ).


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