Sprintax as a whole is a service specifically designed for nonresident aliens and provide different types of forms and returns that you may need to prepare regarding your stay, study and work in the US.
Sprintax offers a few different products such as SprintaxReturns and SprintaxCalculus.
Info: For your income tax return preparation you will need to use the SprintaxReturns product.
SprintaxReturns is a self-preparation software using which you can prepare your Federal and State income tax returns as well as other nonresident forms such as form 8843, an ITIN application, FICA claim etc.