Todayâ??s Ag on the Go is a must have for bird lovers. It is Audubon Birds Pro. This app provides an incredibly detailed illustrated field guide that identifies 821 different bird species, complete with recorded bird calls. The app also comes with seasonal and migratory maps to give you an idea where to find particular species. You can also log your sighting and share them on social media. Audubon Birds Pro is $10 and available on iPhone and Android systems.