Also, good luck getting your short code approved. I watched my co-workers struggle for many months trying to get a short code approved, and there was cycle after cycle of stupid arbitrary demands from different carriers. (It's been a while and I wasn't working directly on it, so the details are a bit hazy, but it was a giant mess and made me feel like we were back in the AT&T monopoly days, where you're a supplicant before the phone company.)