Apnea Trainer Freedive, also known as Tidal, is a specialized iPhone application designed to enhance breath-holding capabilities through structured training. The app provides a personalized training plan that adapts to users' progress, ensuring effective improvement in both physical and mental aspects of freediving. Key features include CO2 and O2 tables, which help users manage carbon dioxide levels and improve oxygen tolerance, respectively.

Users can track their progress with intuitive charts and logs, allowing them to visualize their improvement over time. The app also includes reminders to maintain consistency in training, along with background ambience and real-time announcements to keep users focused. Additionally, Tidal offers helpful guides for both beginners and experienced divers, making it a versatile tool for anyone involved in underwater sports or looking to enhance their breath-holding skills.