The program is suitable for children or non experts. It contains 55 common UK species from very familiar ones like the Housespider to less familiar ones like the Sexton Beetle.
To identify a creature, answer 4 questions about number of legs, wings, main colour and size. If you are uncertain a question can be left as "Don't Know" and the program will make a judgement based on the questions you have answered.
When you press identify all the species pictures are presented as thumbnails in the most likely order with exact matches first, then partial matches, then those that do not match any answer. A box marks the end of the exact matches if any. Press a thumbnail to see the species picture with brief text beneath.
You can leave all questions as "Don't know" to view all species thumbnails in alphabetical order or you can use the separate species browser which has larger thumbnails.
The application uses high quality original paintings by an established wildlife artist. Species images are 320x320 pixels to give acceptable quality on all phone screen sizes/resolutions and views operate in portrait or landscape mode.
Questions are weighted in order of reliability. The legs question, which identifies the generic group, has the highest weighting which means, for example, that the species with the right number of legs but wrong colour come before those with the wrong number of legs but right colour. Other rules provide better ordering and allow for variations between individuals, for example, species with a little of the colour selected appear before those with none.
Questions generally apply to the adult of the species but the application allows for a few cases where the young are commonly found, like the immature centipede which is much smaller and paler than the adult.