I am currently learning Irish with the help of the Android application "Duolingo". It doesn't teach me the grammar; it works with translating sentences. I don't think the app is very useful; I tried it in German, my mother tongue and I often find mistakes and confusing structures. It's not easy to know if a verb is in the infinitive or in the past tense.
Are there any books or apps (for free) where I can learn the grammar of the Irish language? Also I am looking for some pronunciation rules.