Tim,
The other problem is the keyboard. Most Android keyboards don't support the function keys/page up/del etc, that Fractint needs. So I installed something called the "Hacker's keyboard" (free). You have to set it for showing five rows, not four, in order to see the special keys. This works great, and not only that, DosBox Turbo emulates the mouse with the touch screen! You said you have a Galaxy S3, which I believe comes with the Swype keyboard. You should be able to swipe from the Swype button to its adjacent SYM button and get a full set of cursor control buttons. This is how it works on my first-gen Galaxy S phone. Not as convenient, but on a phone, I've been reluctant to give up Swype for a different keyboard.
You can indeed get a Bluetooth keyboard, although they're a shade more practical on a tablet than a phone. (Fractal generation on a tablet... yummy.) Bluetooth keyboards intended for use with Android will come with home, back, search, and menu buttons, which are helpful. --Damien