First things first, I have been using Rocket Spanish for about two weeks now, and I have been very happy with the lessons. I'm probably annoying the heck out of my poor family, stuck at home with me repeating Spanish phrases at my phone and laptop for an hour every day, but such is life nowadays.
I have one suggestion: please include gender/plural/formality indicators on the English side of the Know It! sections. The phrase "I am not going to go with you" (for example) could just as easily be "Yo no voy a ir con tú", "con usted", "con ustedes", "con vosotros", or "con vosotras", without some explicit indicators. I see you've added them to the Flashcards section recently, which is a very welcome development; if you could extend that to Know It!, that would be fantastic.
I have one suggestion: please include gender/plural/formality indicators on the English side of the Know It! sections. The phrase "I am not going to go with you" (for example) could just as easily be "Yo no voy a ir con tú", "con usted", "con ustedes", "con vosotros", or "con vosotras", without some explicit indicators. I see you've added them to the Flashcards section recently, which is a very welcome development; if you could extend that to Know It!, that would be fantastic.