I believe with Clickatell if you have their inbound service you can add extra numbers to the end of the MSISDN, however it’s not recommended as a lot of mobile carriers don’t support it (especially here in the UK).

What you *could* do is send all the different messages from a different originator, then match up the replies to the original messages and do it that way. I’ve done something similar with our SMSBrite site, shout if you need me to talk you through how it’s done.

Alex

I have run into a small problem though. Do you know any way to identify which particular SMS message is being responded to? For example, if I send 3 SMS’s to a mobile, and the phone owner responds to one, I’d like to be able to identify which SMS they are responding to. I’m using Clickatells HTTP api, but can’t seem to figure out a way to accomplish this.

You don’t necessarily have to host SIMs anymore. Many operators will provide cross network Virtual Mobile numbers that can be used for terminating SMS at local rates.

I do agree that 2 way SMS is vital. What other business communication method doesn’t allow you to respond?