the author of this app says:
YuGiCo - Unofficial Yu-Gi-Oh! Cards Guide
YuGiCo guide contains 8900+ Yu-Gi-Oh! cards with images*, descriptions, effects and other data, as well as guide prices to help you become a better duelist and yugioh card trader. Cards database and price information is up-to-date as of September 10 2011 and includes cards from the latest expansion sets Generation Force (NEW), Gold Series 4, Extreme Victory and Dawn of the XYZ starter deck.
We shall really appreciate your comments and suggestions for future versions.
*To use images offline you need to download them after installation, or they will be loaded as-you-go if you are online.
"Yu-Gi-Co - Know Your Cards!TM"
What's New in version 1.0.2
- Generation Force set is added to keep card database up-to-date
- Overall improved stability and user experience
- Requires iOS 4.0 or later.