Below are some screenshots of this app (courtesy of the Google Play Store):
I tested it by making errors in my conjugations to see what would result. The app shows your errors and what the correct answers are by either double-tapping your tablet screen or dragging your fingertip over the verb conjugations.
This app also lets students choose "Random", allowing them to randomly conjugate a verb using any given tense and persons (je, tu, il/elle, nous, vous, ils/elles). It also tracks scores on verbs that students attempted to conjugate as well as verb tenses.
I would highly recommend this app for French students.