Found some!!!
Dragon Island Blue 0.99 (iPad, iPhone, iPod)
Hunter Island 0.99 (iPad, iPhone, iPod)
Monster Island (Not out yet but most likely same as the others)
Micromon 0.99 (iPad, iPhone, iPod)
Zenforms 0.99 (iPad, iPhone, iPod)
My favourite ones are "Dragon Island Blue" and "Hunter Island", both by the same people. There's also "Monster Island" which is in progress (you can check them out on Facebook). In these games, you start with a dragon or monster and go through the island(s), battling others, catching wild monsters, evolving, and there's even some monsters you can mix together to create new monsters! In Hunter Island, there are even bosses you can defeat, and an amazing story line. It's also possible (though really rare) to get the other starters and dragons!
There's also Micromon, which is more like pokemon in the sense that you control your character with the arrows, and walk in grass to catch monsters.
There's also Zenforms (or something like that) which is really good but the story isn't developing any more and there's only a certain amount of monsters.
You could also get the GBA4iOS app for free from their website. (NO JAILBREAK NEEDED) They also have a DS version. They let you play games just like you had a GBA or DS with you. They're having trouble getting through iOS8 though. Apparently it works up 'till 8.1.1
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Hope I helped