One of the special things about the Spanish verb game here at Maestro Spanish is that verbs are grouped based on conjugations. This significantly reduces the number of verbs you have to learn.
For example, verbs ending in -uir, like construir and incluir have identical conjugations. Why should we bother learning them separately? It is much more efficient to group them, and randomly show one or the other during practice. Even better, you start to learn the pattern, so then when you see a less common verb like diluir, you know what to do.
This is one of the key advantages we have over flashcards. While there are only 30ish groups, that suggests you could make flashcards for each group.
Well, first off, that would require tens of thousands of flashcards; I don't know anyone who wants to do that much. Second, you lose the ability to randomly test different verbs that follow the same pattern, as discussed a moment ago.
What are the other advantages to playing? Here are a few:
Different input choices. Sometimes while you're on the go, you can't easily type conjugations on your mobile. With Maestro, you can use the "multiple choice" option and tap your answer.
Quiz specific tenses. Did you know there is a tense mode? Rather than using spaced repetition, you can quiz a specific tense that is giving you trouble.
Better progress tracking. Maestro uses badges to show you progress, both verbs that have been introduced (light green) and verbs that have been mastered (dark green). You can know exactly where you stand.
Full control via options. Want to ignore vosotros? That's an option. Want to make your quiz sessions longer or shorter? The number of "cards" is also an option.
While you still need a complete Spanish practice to reach fluency, Maestro, in my opinion, can form a significant part of a practice routine, and can drastically accelerate the learning curve for Spanish. If you haven't already, give it a go!