Sorry for the sort of general question, but I'm having a hard time figuring out how to start this. I'm trying to incorporate some natural language toolkit code in Python with a mobile app I'm developing in Unity. It's a very small amount of code, but it's critical for the functioning of the app. 
Do I need to have the python code running on some kind of server? How would I go about doing this? I'm very new to python and mobile development. 
Thanks.
Traditional/classic Python is implemented in C. This makes it easy to integrate into any environment that has support for compiled C.
I'm unfamiliar with Unity, but here are some general guidelines on how you would do it with standard iOS and Android.  On iOS, you would just add all of the Python C source files (minus the ones that have a 'main' function) to your project in Xcode. On Android, you would add all of the C source files (again, minus the ones that have a 'main' function) to your project in the JNI part of your project and would use ndk-build to build a native shared library that would be part of your app.
Are you limited to Python? If not, you might want to have a look at Lua as it's much smaller (fewer C source files) and might be quicker to get going.
How can I incorporate Python code in a mobile app?