Not too long ago, after it became known that the Galaxy S III on some carriers wouldn’t be allowed to take advantage of a cloud storage deal, I asked you if you thought that the carriers should start marketing cloud storage as a feature, and include plenty of storage in the process. I am pretty adamant that cloud storage, when handled the right way, is an essential part of the smartphone (and tablet) game these days, because space is a limited resource for some people.

During Microsoft’s Windows Phone Summit, one of the things they revealed about Windows Phone 8 is the support for removable microSD cards. Obviously Android has been taking advantage of this for quite some time, and so has Research In Motion, but we’ve seen some manufacturers shy away from it as they cram memory into their phones without expandable memory, and try to sell it as a 16GB model, or higher in some instances.

This got me thinking: what do you fill your phones up with?

I’m not talking about the things that you can fill cloud storage with and call it good. I’m referring to the things you have to store locally on your phone, whether it’s on your device itself or the additional memory card, so you can use it whenever you want, when you want it.

So what do you fill your phone with? What is the one thing that you can’t live without that you always include on your phone that gobbles up all the memory on your device?

For me, personally, it’s music. No matter how I get access to my music, I don’t have an unlimited data plan so I need to make sure that I’m not streaming as often as I would like. That means I have to store the music on my device, which takes up a lot of space pretty quickly. I can honestly say that while I love applications, I usually make sure that my music fix is taken care of first, and then I’ll add only the necessary apps as I move forward.

When I carried two different devices, though, it wasn’t like that. I had one device, an HTC Trophy for Verizon, which I used solely to listen to music with. It was still able to play music from the Zune Marketplace as long as I paid the subscription cost every month, so that’s all I used it for. That left my main phone, an iPhone 4S at the time, completely open so to speak. It gave me the opportunity to do something with my phone I had never done before.

Install applications. And so I installed a lot of applications. A lot more than I would ever have before, and it had everything to do with the fact that I had the space and it wasn’t immediately “reserved” for the music I knew I always needed.

The result of that was the fact I started buying apps just to buy apps. I started actually going through the App Store and looking for apps that were visually striking, or had a description that made a particular application seem irresistible. I spent a lot more on applications during that extended period of time than I ever had before, and I don’t regret it, so to speak. It was a lot of fun to show off applications like Clear to folks, even if I never had a sound argument for, “But doesn’t the Reminders app already on the phone do that, too?”

“Yes, yes it does. But look how cool this one looks!”

Now that I’ve consolidated my devices down to one, I’m back to focusing on making sure that I get as much music on my phone as humanly possible. While 16GB on a phone sounds like a lot of space, music can quickly eat that up, and sizeable applications can as well. If you play mobile video games then you know that some of them can measure in at 1GB or over in some cases. Impressive to say the least, but space thieves more than anything else.

So where do you fall? Do you use the memory on your phone for music, or applications? Or what about photos? (That’s a lot of photos!) I’m curious to know how you fill your phone’s memory, so let me know in the comments below.