Yeah you can compile your own. That is the whole point.
The examples are mainly there so you, presumably already knowing some code or at least how to work a compiler but maybe just for Windows/visual studio, have something to play with from the basic libraries, maybe something to start to learn how to tickle the hardware so it works, and an idea of the format things want to be in as far as makefiles or just build commands as you have some known working code to play with.
I don't know what we have for starter guides for the 3ds you might look at (there was not much in the way of 3ds homebrew or interest in it -- ios and then android more or less killed DS homebrew and saw 3ds never get off the ground) to get some more ideas on what can be done compared to some of the stuff we had for the GBA and DS but there is hopefully something out there.