My Brute for the iPhone is more advanced in some ways, but there are a number of bugs with the various skills. There are quite a few changes between the web game and the iPhone game.
The biggest difference is that you're limited to a small number of brutes, you're stuck with them unless you delete your entire dojo and start over, and you have to "unlock" brutes 4-8 by recruiting pupils to your dojo. This you probably already know.
Another big difference is that you can't see what the other brute has, because you can't enter another brute's cell. You can't even mouse over their picture to see what their skills are. Fortunately there are a lot fewer of them, so you can learn the weak ones and level up on them for a while, but there seem to be few abandoned brutes and as far as I know there aren't any lists of weak brutes on the web. Most of the time you have just the stats to go on, and that's not much.
In actual game play, the biggest difference is that there are more, and tougher, pets. Everyone gets up to 3 pets pretty rapidly, and you can have any combination of 1 bear, 2 lions, 1 wolf, or 3 dogs. That means anti-pet skills are much more valuable, and on the whole hit points are lower. That in turn means strength is more important, and so when choosing opponents in the arena you're best off just picking the one with the lowest strength.
The last important thing is the animal focuses: I've found that Bear is the best one, it acts like extra-thick skin and if your focus and your master's focus are both Bear, you get double bonuses, which is a really great defense against all those pets. It's nice when you get attacked 18 times by two lions and each one only does 1 point per hit! So definitely get a master, it's really important, and if you'd like to be my pupil I'm a Bear focus dojo and I'd be honored to have you. My code is in my sig.