Deploying React App to Heroku can be a bit tricky, at least for me first time doing it ;). So I've decided to write a blog post to have a reference in future, hope it will help someone as it helped me.
What you need:
1) React app ready to deploy.
2) Make sure node is installed. In my case I specified Node version in package.json(It was required by Heroku CLI):
6) Create .env file in root directory. It will prevent react to build development code
GENERATE_SOURCEMAP=false
7) Now deploy to Heroku. In my case I just linked my dyno with github and pointed to master branch, so each time I push my code to master it will start automatically deploying to Heroku.