Professional Field Guide (Bird Identifier) for 515 bird species inhabiting Europe - from the Atlantic Ocean to the Urals and from the Arctic Ocean to the Mediterranean Sea. The list of bird species included in the app can be viewed at https://ecosystema.ru/eng/apps/21birds_eu.htm

BIRDS IDENTIFIER
The application has a built-in polytomic Bird Identifier (Identification Filter) which helps to determine the unknown bird by 24 different features. You can select the region of Europe the size of the bird plumage coloration streaks beak and feet shape and color distinctive features of appearance behavior habitats location of a sitting bird song and calls daily activity nest size shape construction material and location eggs size and color. The Identifier will help you to narrow down the range of species for unknown bird.

TERRITORY OF USE
The application covers most of the territory of Europe and can be successfully used in the most part of Northern Western Central Southern and Eastern Europe including Scandinavia Baltic States France Spain Balkan countries Transcaucasia Northern Kazakhstan and other adjacent territories.

20 EUROPEAN LANGUAGES
The app is composed on 20 European languages including English German French Spanish Italian Hellenic and others. The user can choose any of these languages.

BIRDS CALLS
For each of 515 bird species the app provides one combined recording including male songs and several most typical calls – alarm aggression interaction contact and flight calls etc. Each of the recordings can be played in four different ways: 1) once 2) in a loop without interval 3) in a loop with an interval of 10 seconds 4) in a loop with an interval of 20 seconds.

PHOTOS AND DESCRIPTIONS
For each species a several photos of the bird in nature (male female or immature bird in flight) distribution maps and eggs are given as well as a text description of the appearance behavior features of reproduction and feeding distribution and migrations.

QUIZ
The app has a built-in Quiz which can train you to recognize birds by their voices and appearance. You can play the quiz repeatedly – the questions for recognizing species alternate in random order and are never repeated! The difficulty of the Quiz can be adjusted – change the number of questions change the number of answers to choose from turn on and off bird images.

IN-APP PURCHASES
The main functions of the application are free - for each species of bird you can view its image and text description and add species to Favorites (these functions are available offline) as well as play a recording of its voice (if you have an Internet connection and no more than 1 time per minute). Paid functions allow unlimited use of the Identification Filter and Quiz open access to additional color images and also make it possible to play all recordings of bird voices offline. You can purchase access to all bird species (the "All Birds" group $12.00) as well as to any geographical ($7.00) or systematic ($2.50) group of birds.

THE VOICES OF BIRDS CAN BE PLAYED IN NATURE!
In the presence of the Internet the voices of birds can be played directly in nature. After paying for in-app purchases all functions can be used offline including in the areas without the Internet - on ornithological excursions walks in the country on expeditions hunting or fishing.

THE APPLICATION CAN BE TRANSFERRED TO THE MEMORY CARD (after installing the application).

THE APPLICATION IS DESIGNED FOR:
* birdwatchers and professional ornithologists;
* university students and faculty at on-site seminars;
* teachers of secondary schools and additional (out-of school) education;
* forestry workers and hunters;
* employees of nature reserves national parks and other nature protected areas;
* songbird lovers;
* tourists campers and nature guides;
* parents with their children and summer residents;
* all other nature lovers.