The present study examines the discourse of a number of Short Messaging Service (SMS). The selected data is analyzed according to the lexico-grammatical choices reflected in the interpersonal metafunction. Results are, then, interpreted for the purpose of deciding how service providers use language to convince a large number of customers of their digital products. Such accomplishment is conditioned by how much they succeed in persuading their audience that they are capable of providing them useful products and how these products, in turn, meet their communicative demands. The study assure that the selection of the lexico-grammatical tools is crucial in enabling senders to perform a number of functions such as constructing social relations, exercising power or maintaining solidarity with the receivers.