Noisli might be a bit more popular than openHAB. We know about 1 link to it since March 2021 and only 1 link to openHAB. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
You can start on a general home automation like openhab.org. Source: almost 2 years ago
I use a website called noisli.com for the background noise. You can give it a try if you would like to. Source: about 1 year ago
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Noizio - Feeling that the noise of the big city is too much for you to bear?
ioBroker - flexible and modular application for the IoT and Smarthome
MyNoise - Custom shaped online noise machines. Many Many generic sounds
Google Home - Set up, manage, and control your Chromecast, Chromecast Audio and Google Home devices.
A Soft Murmur - Ambient sounds to wash away distraction.