Right now my org uses SMS Magic, and we've used it to schedule mass SMS blasts manually.  What I'm trying to accomplish instead though is this. 

I have a module called "Clients", and in the module I've added a field calld "SMS Type". This "SMS Type" field controls the content of the SMS they receive. 

1) I want all clients who have the value "SMS Type 1" in the "SMS Type" field to receive a certain SMS on the 25th of every month! So essentially I want to schedule a mass SMS blast using SMS Magic, but this SMS should only go out to people under the "SMS Type 1" category. 

2) I also want these SMS sent to trigger a workflow. I created another separate numeric field called "No. of SMS received". Everytime a scheduled SMS blast is received by this person, I want the count in the "No. of SMS received" field to increase by 1. When the count reaches 3, I want the "SMS Type" to change to "SMS Type 2" instead. 

I know exactly what I want to do - I want to schedule a selective mass sms blast, and I also want a certain workflow to be run on recipients of said SMS blast. However, I'm at a loss as to how to begin executing this. I figure surely someone must have attempted something like this before. I'm all ears for ideas and suggestions!