Here is a list of all the major pony characters that appear in the cartoon and their pictures. The list is small, but I'll add more soon.
Applejack--An orange earth pony with yellow hair. Has apples symbol. Naturally, likes picking apples.
Bowtie--A blue earth pony with pink hair. Has pink bows for a symbol.
Bubbles--A yellow earth pony with blue hair. Has blue and green bubbles for a symbol.
Cotton Candy--A pink earth pony with pink hair. Has white circles for a symbol.
Ember--A baby purple earth pony with pink hair and no symbol.
Firefly--The most famous My Little Pony of all. Firefly is a pink pegasus with blue hair and lightning bolts for a symbol. She is very brave.