I am always looking for Chinese language education resources. Here are my reviews of and links to information about the learning tools I use regularly.
For many simple searches for words, characters, and meanings, my Dian Hua dictionary is a perfect solution. However, there are times when the CE-DICT on which the app is based is not good enough. That's why I purchased the iCED Pro iPhone app which is based on the more complete (and more expensive) ABC dictionary.
There is no shortage of flashcard applications for the iPhone. You can purchase apps that are sets of cards, apps that are compatible with various card sets, and apps that include (with other features) a flashcard capability. In fact, my personal favorite Chinese dictionary for the iPhone, the DianHua Dictionary, was recently updated to include a flashcard maker that works with it's bookmark function.
Because the CEDICT dictionary is available as a free resource, there are numerous Chinese-English dictionary apps on the iTunes App Store. Most of these apps are roughly the same and range in price from free to about 4 dollars. A few of these apps will include extra features such as bookmarking and simple flash cards. One of the best that I have found is the DianHua Dictionary.