Halcyon — Mobile App for Sleep Coaching
How setren designed a calming, accessible sleep coaching app that achieved a 4.8-star rating and 62% Day-30 retention in its first three months.
The Challenge
Halcyon is a sleep wellness startup founded by a sleep scientist and a behavioral psychologist. Their coaching methodology was clinically validated but existed only in PDF worksheets and Zoom sessions. They needed a mobile app that could deliver personalized sleep coaching at scale — guiding users through a 6-week program of sleep hygiene habits, cognitive behavioral techniques, and relaxation exercises. The app had to feel calm and trustworthy in a category full of overstimulating designs. And it had to work for users who are, by definition, tired and struggling — accessibility and simplicity were not optional.
How setren Approached It
We started by going through the 6-week coaching program ourselves. Two team members followed the full protocol to understand the user experience from the inside. This shaped every design decision. The visual language uses dark, muted tones — deep navy, soft amber, and desaturated lavender — to avoid the bright screens that suppress melatonin. We set a minimum touch target of 48px and a maximum of three taps to reach any feature. Typography is large, high-contrast, and optimized for bleary-eyed reading at 2am. The information architecture follows the coaching program's natural rhythm: evening wind-down routine, sleep diary entry, morning reflection. Each session is 5-8 minutes. We designed a gentle notification system that nudges without nagging — the app learns the user's natural bedtime and adjusts reminders accordingly. The audio experiences (guided breathing, body scans, sleep stories) were designed with a sound designer to use binaural frequencies that research suggests support relaxation.
The Result
Halcyon launched on iOS in September 2024. The app reached a 4.8-star average rating within the first month, with users specifically praising the calm design and the quality of the coaching content. Day-30 retention hit 62% — exceptional for a wellness app where the industry average is around 20%. The 6-week program completion rate is 44%, more than double what the founders achieved with their manual coaching practice. Halcyon has since raised a pre-seed round and is preparing an Android launch using the design system we built.
“Most designers would have made it pretty. setren made it therapeutic. They understood that every pixel affects how a sleep-deprived person feels at midnight.”
Tech Stack
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We design apps that respect the user's state of mind. Accessible, calming, and clinically informed — because good design is good care.
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