You can use this app for sleeping, power nap, meditation, concentration, reading or just relaxing.

Contains high-quality relaxing sounds (all free) for any mood, divided into the following categories:

★ Rain sounds
★ Ocean sounds
★ Water sounds
★ Night sounds
★ Countryside sounds
★ Wind and fire sounds
★ Relaxing music
★ Traditional sounds
★ ASMR sounds
★ City sounds

and more