30 Letters - Serbian cyrillic vs. latin alphabet, also IPA transcripted.
Plus - 8 serbian/croatian latin letters which differ from english alphabet.
Plus - 9 russian letters which differ form serbian cyrillic alphabet.
INCLUDED: cyrillic/latin keyborad buttons & single-sounds AUDIO.
PRESS CAPS LOCK: (if not you'll see small latin letters: some latin majuscules = some cyrillic letters) - cyrillic small caracters are equal to the majuscules, only smaller.