I recently purchased an iPhone and came across a few vocabulary builder applications. However, what happened to using regular index cards to study new vocabulary? When I started to learn Spanish in high school, I was a huge fan of flash cards. Not only were they inexpensive to make, I could take them wherever I went.
When learning a second language, it is important to acquire new words. Cannot have much of a conversation if you have a limited vocabulary! I am currently sitting in on a Catalan class at East Carolina University and flash cards have become my new best friend.
Instead of creating flash cards that just have the Spanish word and the translation in English on the reverse side, why not draw an image instead that conveys the meaning? You could also include sample sentences using the word on the card to help you understand how it is used in actual conversation.
Please let me know if this helps with the second-language learning process!