If you’re willing to pay, iKnow is efficient, and there’s a mobile app. I went with anki decks for the first year of learning and for some reason I wasn’t able to stick with it. You might have better luck than me. iKnow has a core 6k ordered by what seems to be difficulty and frequency. If you’re using WK though it can be a lot easier if you separate the decks by WK level, which I’ve done here and you can use.
But to answer your question, there are three courses in there for vocab words without kanji. If iKnow fits your style, then the No Kanji decks will teach you 929 words.