Window tint is a dyed product that absorbs energy from the sun. This is very bad for your home windows as it can add too much stress to the glass.
Window tint can be used on vehicles though, because vehicle glass is tempered or heat strengthened. Tempered glass is much stronger and can be subjected to the stress of a window tint.
Window film is used in homes because house windows use float glass, and when applied with window film, will not break. Window film products are designed to reflect solar energy rather than absorb it. Window film absorbs about half of the energy as a window tint will, making it safe to use.