Some kind of service to receive sms messages.

Hope nobody mind I'm posting to the C# forum, since I do not have a clue how / if the following can be done.

Hoping that it would be possible for mobile apps to send out automated text messages (long story) I was wondering if / how / what one can create (or service one can use) to look for text messages and act according to the number the message was sent from.

It's all part of a "panic" service thing and at present the mobile app will call a method on a web api I created which then alert the emergency service call center.

While this all work, I'm worried that user's without an internet connection can push that panic button until they are blue (literally and figuratively!)

Any advice / ideas / critic / tips / thoughts?

ps: While I should ask them if they could deal with it, we do have an sms provider, though using them to send sms messages, not receive it.

Well, I would look at the mobile platform you are targeting. Odds are there is an API that exists that will let you send SMS messages. If that doesn't work, you would really have to research SMS specifications. Normally when you research the topic, you will find a lot of information you need in order to get it to work.