This app was mentioned in 4 comments, with an average of 1.25 upvotes
I always laugh at this. I can't sleep unless I have a fan on. When I travel for work, I have the Sleep-Fan app on my phone. That has been a life-saver for me. I can't stand total, ear-ringing silence.
No so much a "here it is on amazon" but there are apps that make fan noises, my daughter used one but since moved to A Soft Murmur which makes wave, wind, thunder storm, fire sounds instead. It maybe an option to leave your phone on charge playing sounds and save yourself $30?
https://play.google.com/store/apps/details?id=com.sleep.fan
https://play.google.com/store/apps/details?id=com.gabemart.asoftmurmur
https://play.google.com/store/apps/details?id=com.sleep.fan
Not the same as real deal, but close enough.
There's lots of apps for it. We have one one for or daughter on our Kindle for when we go on trips ;-)
https://play.google.com/store/apps/details?id=com.sleep.fan&hl=en