What are some really good photo editing apps?

[Lucy]

So I was looking for one, and there's this girl on instagram and she had these cool little designs on her photos, lets say some white flower patterens and such. And she can also make her photo foggy and in the center there's a logo. She won't tell anyone what it's called so I was wondering if any of you can help. Oh and she can also add cute simple words and diagrams in pics such as a heart surrounding words. And she can also add a semi transparent logo in pics.