Before your first encounter with a prospective new employer here are a three things you must do to be a serious candidate for the new job:
Use the product of service. Download the app (an use it) or sign up for a 30-day trial (freemium models) and experience the product of service first hand. Jot down your top 3 favorite things about the product or service and talk about them in your face-to-face with the hiring manager.
Read the employer website. Read a few case studies or use cases. Learn their value proposition, competition, values, culture, stakeholders, news, growth, verticals, investor news. The more you content you absorb or digest should trigger confidence and genuine enthusiasm.
If you really want to make a great impression, prepare a 30-60-90 plan (for how you will sell product or service) that you will implement on day one.