Instruct: Classify a given Amazon review as either positive or negative.
Query: Good vocab review for intermediate learners

This is a nice tool for beginners and intermediate level learners of MSA, but if you've been studying for a while you will find this a bit frustrating. The 4000 words utilized are good, but they won't take you to the next level. The lists are good, but it would be nice to be able to make your own. A section of Arabic proverbs would be very useful as well, as knowing them makes a real difference when dealing with native speakers. I would pay $25 for this, but no more.