How do I sell my web app?

Hey HN, I am building a web app specifically targeted towards SMB and Startup marketing teams. This web app create a public content calendar. It's cheap with price tag of $25 and $45 per month. Total annual spend would be $300 to $500.

I experienced that reaching out via email does not work well for us. LinkedIn works but then it is hard to get meetings for such a small amount.

What are your tips, techniques, and mechanisms for selling small web apps? Share your tips to help me understand marketing better.