Book about a girl with purple eyes whose father was a (prince?) alien from a different world. I think the cover was either a greyscale purple eye or a purple crystal. She met a boy from the other world who was a prince(?). She was hunted by people from the other world as well(?).
From the minimal clues provided:
Book about a girl with purple eyes whose father was a (prince?) alien from a different world.
Check. The protaganist, Karan, had purple eyes signifying she was descended from a Charon, a race from a different world. Her father was, I think, one of that race.
I think the cover was either a greyscale purple eye or a purple crystal.
She met a boy from the other world who was a prince(?).
Half a check. Early on she meets Llian who's neither a prince nor from the other world. They spend most of the series together.
She was hunted by people from the other world as well
Check. Due to her Charon nature, she was pretty much hunted by everybody
Not a complete match, but given that the question is a bit terse, still worth putting it into an answer: Stargazer (2014) by Melanie Matthews?
Ava is an anomaly. She has the appearance of the enemy alien race known as Stargazers, with her lavender hair and eyes, but the human capacity for love and forgiveness. Ava has amnesia—not knowing who she is or where she came from. She rejects that she’s a Stargazer, but she isn’t entirely human either, with the strength to crush a man’s bones. The key to everything lies with the dictator Julius Pallas, who orders her torture and imprisonment inside the doctor-ridden mega-facility known as the Corporation. When the two finally meet, Ava will discover her true identity and her connection to him. He’ll discover how greatly she’s changed, and how her destiny may just ruin his murderous empire.
- girl, purple eyes, alien-related;
- according to this review, Ava is a Stargazer princess. Having not read the book, and info on it being scarce, I wouldn't be sure, but it may be due to her having a "royalty" father;
- cover features a purple eye:
Not sure if checks:
- two of the named boys I could find were John and Victor, but browsing the Google books extracts don't seem to yield much about them being alien princes as well;
- she doesn't seem to be hunted, but all the men "desires" her in some way, so perhaps it could be qualified as a chase...
Found with the Google query
book "purple eyes" alien prince site:goodreads.com and looking at the Google Images results, the cover looked promising as it partly matched.