Good for a quick refresher
This is the free version of Grammar Up. The app itself is very easy to use and straightforward. Students can choose from ten different grammar categories, and test themselves with five to ten questions for the category they select. This app is good for a quick refresher on something like conditionals, prepositions, etc. I would recommend it for a student just needing to see a few examples to get over the hump on figuring something out in an English class or any class where papers are written. However, you really do need to upgrade to the paid version to be able to rely on this for your day-to-day grammar needs. The full version has over 1800 questions and 20 categories to choose from.
austroud about
Grammar Up : Lite Edition, v3.0