After a week since the launch, I gathered feedback and update the app and the landing page a bit. Then I share the app to Product Hunt.
https://www.producthunt.com/posts/devutils
There weren't many comments on the post, but it managed to reach ~100 votes, and get itself to #3 product of the day. I consider this a success.
I have no idea how many orders did I get from Product Hunt since I don't add any kind of tracking code to the landing page.