If I don't make any money off my apps, can the patent trolls still
troll me for intellectual property and what not?
Yes. Let's be clear with the language: they can sue you for damages (money). Prior to actually suing, they can request a legal arrangement in which they license the patented software component to you, for a per-copy fee. Or a flat fee. Or whatever they want to offer as an arrangement. They can name any price they want. And defending a lawsuit costs money, often a large amount.
(Well, in some sense, any person can sue anyone for anything; that's not to say that they will win the suit, though. Still, what I describe above does not fall into the category of frivolous lawsuits--though there are many who wish patent trolling suits would).
Of course, this is not cost-free on their side, either; and so the points in the other answers about the likeliness of this happening to a free and open source or free software project are something to consider. It did happen in the Jacobsen v. Katzer case, though. For some sense of probabilities, you might want to look at the recent paper by Colleen Chien
I've read that I should incorporate in my state as LLC.
You can form an LLC in your state or any state of the U.S. However, one of the requirements for a properly formed LLC is that the company have sufficient funds in its account to handle potential problems such as debts or defenses of lawsuits. If you have a one-member LLC that that makes no money, has no mechanism for making money, and has no funds, it is possible a judge will pierce the corporate veil and find it is merely an alter ego of you, and then you would be personally liable for whatever damages are awarded in a suit.
[Obligatory I Am Not A Lawyer footer]