From the Store description:
You can flip through a list of common butterflies and day-flying moths in Britain and Europe, search by name, or use a filter to narrow down your search by colour, time of year and size. No need to wait until you get home to search through a field guide while trying to remember what it looked like! When you've identified your butterfly you can add it to your "collection" (don't worry - no butterflies will be harmed), and we'll automatically record the time and location of your sighting. And just to make it even more fun for kids and adults alike, you can score points depending on how rare the sighting.
Here it is in action - no surprises, just butterflies all the way....
There's a terrific splash screen, but it swivels out of the way VERY quickly, I was only just able to snatch it as it rotated! (right) the graphical main menu...
Getting going - perhaps the most innovative way in is via picking wing and secondary colours and seeing what 'matches'...
In this case, a common-or-garden Wood White!
As you spot butterflies, you can add them to your collection - for fun, rarer varieties score more 'points', which you can use to compare against the tallies of others. No cheating, please! (right) if you half know the name of a butterfly then you can do a more traditional search...
Each butterfly is illustrated and detailed, as needed, and you can browse via common names or (right) sorted by Latin name, if you want to go all scholarly....
Butterfly Spotter is ad-free and doesn't rely on a data connection, so it will continue to work in the field. As the developer says, "It's like having a Lepidopterist in your pocket!"
You can download Butterfly Spotter for free here in the Store.