Do you have an iPhone? Or an iPod Touch (Good God - don't call it an iTouch or you'll be accosted by an Apple fan). Maybe you even have one of those iPads.
If you do have an Apple device and are studying Japanese, there are a lot of ways to make the most of this awesome tool!
I broke down and bought myself an iPod Touch last month, and though I haven't quite joined the Cult yet, I am quite satisfied with it. Although I haven't been using it exclusively to improve my Japanese, that was the justification in my mind for buying one. So I have been exploring the ways in which this iThing can best be used to supplement our Japanese studies.
Right off the bat, I'm going to recommend you change your settings. The iBeast is available all over the place now, so it comes set up with a spate of language options, no matter where you buy it. If you're feeling confident, just go ahead and mosey on down into your General Settings area and change that to Japanese. Not only does this change your system language to Japanese, but a surprising amount of games and applications come with a Japanese version.
You're also going to want to set up a Japanese keyboard. There's a button in the General Settings area, right near the language settings, that allows you to add additional keyboards.
The Japanese keyboard takes a little getting used to but can really make inputting kana a lot easier.
If you're particularly partial to kanji, you can also install the Chinese keyboard which will allow you to write them in. It's pretty sensitive to stroke order, however, so unless you're really good it can be hard to use (I'm not, so it is for me). I also imagine you won't be able to get some kanji, since there are slight variations between some Chinese and Japanese characters.
If you're using your iDevice for study, chances are you're already familiar with Kotoba! and Anki, but I'll err on the side of safety and mention them anyway.
Kotoba! is a free application that contains Japanese-English and Japanese-several other language dictionaries, as well as kanji look-up by both reading and radical pieces. One of the things I like best about Kotoba! is that the top menu bar contains a little star that you can click to add any given entry to your Favorites list, which you can then go back and view at any time. Perfect for saving words that you want to add to your SRS program later.
Speaking of SRS (Space Repetition Learning Systems), if you use your computer to study, chances are you know of Anki. There's a free version you can use on your computer that has become quite popular. There's also a version for your iWhatsit, but it's a little steep for an app - $25. Still, if you use SRS as part of your normal routine, it's probably worth it. You can sync it with your computer and use those same decks on the go. My only complaint is that, as far as I can tell, there's no way to reset your deck or make a new one from scratch on your iProduct, although you can add cards to a pre-existing deck.
I also just purchased another app that you may not be aware of. It's called KanjiBox and is an improved iVersion of a Facebook application by the same name. Essentially it's a program that lets you set a level (for now either Sensei, or JLPT N1-N5) and quiz yourself on kanji and vocabulary. It has a number of features, not all of which I've tried yet, including a flashcard program that remembers and presents you with the words you got wrong in the quiz section.
Last, keep in mind that all work and no play makes Johnny bored. And we don't want to get too bored with our language studies. If you're going to slack off, at least try to increase the chance that you'll be slacking off in a way that exposes you to more Japanese.
As I mentioned, there are a number of games that are available in multiple languages. I already briefly talked about Game Dev Story, a nifty little sim game that can easily eat hours of your life. I also picked up SquareEnix's Final Fantasy-themed Crystal Defenders game, a very difficult tower defense game. May want to try the lite version before you pay for it. A friend of mine, curse his existence, also convinced me to buy Zombie Farm, a spin-off of the popular
crackwhore Facebook game FarmVille. Except it has zombies, which you can "grow" and attack other farms with.
Both of these games (surprise surprise) change to their Japanese versions when you switch from English to Japanese on your iJigger.
Hell, you can even use the increasingly popular Instagram in Japanese. Though I haven't exactly been able to verify that. Apparently you need to register online before you can use this app, and I don't have any wifi available. If anyone knows how to use if offline, please do tell.
This is what I've come up with so far. Do you have any other tips or useful application recommendations? If so, please share in the comments, as always.