I like to stay healthy and one way I do that is by walking or running. Sometimes it would be convenient to do prayer just wherever I happen to be.
Question: Is it permissible to pray on the sand at a beach or on the grass at a park?
As I understand, I don't need to worry if people see me pray. But I'm not sure if praying on sand or on a patch of grass meets the condition of a clean place to pray.
Some Google hits suggest it's okay (e.g. this), but they're random people on forums.