Customised addon for sign language

We want an add on SKYPE which will be used for HEARING IMPARIED communication. for instance, an HEARING impaired person goes to an office, where no one know sign language. The said person get connected from his ipad to us/ call center. He put his question to call center via sign language. The person at call center understand sign language and is able to understand his query. The call center person then send message on the same ipad in normal speech, which the other person is able to hear via head phone/speaker and vice versa. This will work via Skype and we need an application to communicate between call center and ipad and vice versa, with few options to start with. It will be in two language and one will be English. Other language is yet to be finalised. This data needs to be saved.