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The free app, Learn Czech 6,000 Words (which shows up as "Czech Fun Easy"), has a great format for memorizing lots of nouns and some adjectives. I know it's on Android, and I suspect there's also an iOS version. Be aware that the words are not prioritized by frequency of use.
The 200+ page book available as a PDF, A Grammar of Czech as a Foreign Language, walks you through the major features of the language.
The CzechClass101.com video series on YouTube tests your listening skills on short conversations.