I made a really simple, pseudo GUI using pythondialogue (its a wrapper for whiptail for bash), I need it to be cross platform between linux and Mac OSX. The main issue is its really hard to find information on pythondialogue, the only documentation seems to be on their own site. I would just use whiptail, but I'm learning python so using this to hone my python skills. 
What I like about pythondialogue (and whiptail) is that its not really a GUI, just a dialogue inside the CLI, so it can used purely through the command line such as if you SSH to the computer you want to run it on. Can tkinter do this too? 
Either way, a big thing I'm wondering is what benefits tkinter would provide over regular pythondialogue. Obviously the difference is it lets you create proper GUI applications, but would it be wisest to only create a GUI application in cases where its absolutely necessary? 
tkinter sounds like the easiest way to code GUIs in python. What disadvantages does it have to PyQt or wxPython. I wan't to start developing mobile apps as soon as possible and I see iOS and android apps can be written using python and Qt can be used to write both Android and iOS apps. So with this in mind, would learning PyQt mean I would also be developing the skills I'll need to create iOS and android apps? If so, this is most definitely what I'm going to do.
Learning PyQt will definitely help you learn to create IOS and Android apps. Even more, PyQt comes with QtDesinger which is a visual editor for creating apps with minimal coding. Tkinter in my perspective is for very light GUI programming. If you feel like you want to make money of these apps, I would highly advise you to check out Kivy.
Python - pythondiologue vs. tkinker vs. wxPython vs. pyQt