CLICK TRACKING SOFTWARE FOR MOBILE NUMBERS

I require some type of script to be written to track who has clicked links from an SMS . so when we send our marketing messages to our subscriber lists via SMS we direct them to a URL, but we can only track how many clicks we have had rather than where the click came from. so we need some type of click tracking script/software, we have seen it work for a competitor, ( they seem to have a unique link next to the URL for every persons mobile number. thank you