Our service (frucall.com) heavily relies on SMS, and I had very bad experience with ClickATell. While their web site looks pretty legit, their service is very unreliable (and by the way they never sent us the refund after we canceled with them).

It is important to notice that 2-Way SMS in the US has strict regulations - you have to use a short code, otherwise your service is considered illegal and the carriers can shut you down. ClickATel does not operate based on shortcodes, they use SMS modems which is basically a way to hook up a cellular line to a computer and intercept SMS messages.

There's quite a bit of details that one should be aware of if one wants to run a business grade SMS service in the US due to the way carriers control the SMS traffic. If there's interest from the readers I'll be more than glad to write down some of the details.

If you wouldn't mind, I'd find that very useful. I live and work in non-US markets, and US carriers' behaviour strikes me as idiosyncratic and frankly bizarre :)

We've had a good experience with Clickatell, but only used them to send verification SMSs to our worldwide users.

In the US, a Clickatell SMS will come from their shortcode, which is perfectly fine. No need to pay big bucks for your own shortcode, like some SMS providers want you to believe.

If you need to receive SMS, it's a different story. You could get a UK number, which is much cheaper then a US shortcode, but might look weird to your US users.

Yeah, I would love to know more about it.

I would be interested as well.