We have created a scheduling DApp similar to Calendly. It enables users (owners) to conveniently share their schedule with others (requester), and requires a deposit (placed in escrow) to book somebody's time. If the meeting occurred the owner can return the deposit. If the requester was a no-show then they can burn the deposit.
The DApp uses NextJS, React, and TailwindCSS for the interface. Moralis takes care of the database, authentication, and all the RPC connection headaches. The react-moralis package was especially helpful in keeping the codebase easy to understand, while giving us the power of Moralis. Hardhat for compiling/testing the smart contract. This was especially nice because we were able to build out solid tests and trust that the smart contract would work while we shifted attention to other things. This was our first tie deploying to polygon, and we'll definitely be deploying to polygon again. The deploys were easy and the costs are low, especially on the test net :)