While research tends to go back and forth on the advantages of noise versus silence for creativity and productivity, I always find myself more relaxed and focused at work after turning on a light amount of ambient sound, usually with some combination of rain, fan noise, and white noise. That habit has turned me into somewhat of an ambient sound connoisseur. Too many ambient noise apps come with cheap sound effects, annoying commercial breaks, or exorbitant subscription fees
Link:
The best 11 ambient noise and music apps to help you stay focused