Hmm
Not an 'app' in any interactive sense of the term but rather a narrative of static pedantic and uninspired material grouped in a few subheadings.
Yes, Russian Grammar is completely free and it doesn't have any in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
Russian Grammar is free.
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Not an 'app' in any interactive sense of the term but rather a narrative of static pedantic and uninspired material grouped in a few subheadings.