Fluttering onto a smartphone near you soon, a field guide to the butterflies of Northern California, created by UC Davis students.

"I hope that teachers will be able to use it for classroom projects," said Melissa Whitaker, a UC Davis graduate student who developed the app with two computer science undergraduates, Joey Jiron and Bryan Maass. The app was released to the iTunes store this week. It can be downloaded from the store for free.

The app includes photos and descriptions of adults and caterpillars of 117 species of butterflies found in the San Francisco Bay Area and Sacramento Valley. It draws on three decades of data compiled by Art Shapiro, professor of evolution and ecology at UC Davis.

The app can be used to look up butterflies by common name, scientific name, family and color. The app also allows users to enter their own notes and photos and record sightings. Whitaker hopes that the app will ultimately be able to collect users' observations and photos into a publicly accessible "citizen science" database.

"It's been a great learning experience for me," said Whitaker, who had no prior iOS programming experience. The team is releasing the software as open source, so that it can be used by others as the basis for other natural history field guide applications.

"It was a lot of fun," said Jiron. "It's given me a taste of the real world, working with a client who is coming from a different side of things."

Also on the team is David Waetjen, a Web developer with the UC Davis Information Center for the Environment. Waetjen will work on the second phase of the app, in which users will be able to upload photos and notes to the public database.

The project was funded by the National Science Foundation-sponsored Integrative Graduate Education and Research Traineeship in Rapid Environmental Change, or REACH-IGERT, at UC Davis.