I love the idea of white noise or frequencies for relaxation. Personally many times been going to sleep with rain sounds.
This is a bit of an augmented concept. Adding vibration patters that "match" the audio frequencies –as much as possible– makes it a very different but pleasant exeperience.
I'd love to see what you think about it.
Show HN: Feelquency – Mixing calming frequencies with soothing vibrations
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