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. The app currently costs an astounding 35 dollars. It was 30 when I purchased it (I bought in with the previous version). The cost is the result of the license for the ABC dictionary, which was developed by a professor at the University of Hawaii. This reference has many more entries that CE-DICT, but that comes with a price. The entries are also much more detailed and specific with codes for grammatical classification, example uses, and cross-references to other entries (something that Dian Hua has added in recent versions).
The most recent version of the iCED app took a step backwards in usability. I'm not sure why, but the interface has become overcomplicated. The original version was simple and perfect. Since the new version came out, public demand has made the developers revert some of the interface, but they have resisted a complete reset to the original. We can still hope. For everyday use, I find the Dian Hua dictionary easier. However, when I run into a less common word or phrase, the iCED ABC Dictionary is a must. There is one other iPhone app that also has a license for ABC, but the interface is even less useful. For now, this is the best option.