Colibri is an iOS application designed to help you rapidly build German vocabulary knowledge. The application uses spaced repetition to optimize learning speed and provides analytics of your progress over time.
It differs from other vocabulary learning software in that professionally curated word sets with example sentences can be bought for varying skill levels. Colibri also includes important contextual information, including verb forms and noun articles/plurals, and color-codes nouns by gender as a memory aid. Try it out for free on the App Store.