Noizer is described as 'lets you to mix multiple ambient sound sources to create the perfect mesh for relaxation and focus. Mix sounds like fireplace, birds or even a bar and street, all adjustable with individual volume sliders'. There are more than 50 alternatives to Noizer for a variety of platforms, including iPhone, Android, iPad, Online / Web-based and Android Tablet. The best alternative is myNoise, which is free. Other great apps like Noizer are Blanket (Free, Open Source), A Soft Murmur (Freemium), Tide (by Moreless) (Free) and Rainy Mood (Free).
ANoise is a minimal ambient noise player to help you focus on your productivity! Just open the Ubuntu sound indicator and choose your noise: Coffee Shop | Fire | Forest | Night | Rain | Sea | Storm | Wind
Blissful noises is a free online background noise generator. It offers various relaxing sounds divided into environments that helps you meditate, focus or chill like white noise, binaural beats, rain, thunder, bird, ocean, etc.