If you are a novice or intermediate spanish student who, like I did, struggles with the different conjugations of verb tenses, this app is indispensable. Exploring Spanish: Irregular Verb Tenses provides the user with flash cards for common irregular verbs as well as a 400+ question quiz for irregular verbs in the present, preterite, conditional, future, and imperfect tenses. Some of the verbs included are: ser, estar, conocer, tener, venir, salir, jugar, dar, ver, decir, and more! Best of luck.