Outside of the design and the shape of the island on which things take place, it's connection to Peter Pan is superficial at best, for the scenario that plays out here, and even the character of Tinker Bell herself, are frankly incompatible with anything that went before.
The pixie, created by J.M. Barrie but repurposed as the Disney mascot soon after the release of their "Peter Pan" adaptation, has long been a top money maker for the studio, adorning all sorts of merchandise, most recently a new "Disney Fairies" line of products; in this sense, a Tinker Bell movie was inevitable.