Breathly - Just Breathe is a free and open source breathing trainer for Android developed by Matteo Mazzarolo. It is designed to help users relax and train their breathing through guided exercises. With no ads or in-app purchases, Breathly is a straightforward and accessible tool for those looking to improve their mental and physical health.

The app offers a variety of breathing techniques to choose from, each with a different focus and duration. Once a technique is selected, the user is guided through a simple and easy-to-follow exercise. Breathly also offers customizable settings, allowing users to adjust the length and pace of their breathing exercises to their liking.

Overall, Breathly - Just Breathe is a great option for anyone looking to incorporate breathing exercises into their daily routine. Its straightforward design and open source nature make it a valuable tool for those seeking to improve their mental and physical well-being.