Case study · AI / voice ML · Parenting tech
Cappella: Android cry detection for an MIT-founded baby-care startup
Contract senior Android engineer (Jun–Oct 2024) for Cappella — “Empowering Modern Parenting with Sustainable Tech.” Finished the Android product surfaces, wired voice ML on the baby-device path, and helped land the Google Play launch. Credited by name on the founder’s Android launch post.
- Play launch Jul 2024
- Voice ML cry path
- Named on launch post
Product
Cappella (Cambridge, MA; founder Apolline Deroche, MIT Sloan) was an AI parenting brand: a two-phone baby monitor that reuses devices parents already own, plus an AI cry translator and routine tracking. The company built a hospital-collected dataset of 5,500+ labelled infant cries across six need classes — hungry, tired, in pain, lower-body discomfort, upper-body discomfort, and respiratory disease signals — with clinicians in the labelling loop.
Positioning on LinkedIn: sustainable tech for modern parenting, CES 2024 demo lineage, and an all-in-one app so parents are not juggling separate sleep / feeding / diaper tools.
Problem
iOS led; Android needed an experienced engineer to close the remaining task list and ship. A substantial Kotlin codebase existed, but launch depended on baby-device cry detection, care-tracking UX, audio library work, Java ML library integration, and a long tail of auth / profile / rotation bugs.
What I shipped
- Baby-device cry detection — mic capture through voice ML / cry-classification models (Kotlin + Java libraries) into parent-side results and notifications (hunger, tiredness, discomfort, and related needs), matching the Results / confidence UX shown in product marketing.
- Two-phone monitor — baby profile and device path for crib-phone vs parent-phone.
- Care tracking — feeding, sleep and diaper logging with Tracking Summary graphs and emotional-state insights.
- Soothing audio — sound library and gallery (music, white noise, parent voice).
- Launch hygiene — signup/login, profile edit and photo, logout, privacy policy, screen switching and rotation fixes for Play readiness.
- REST-backed flows — Android client wired to backend services for accounts and product features.
Public product features (launch messaging)
- AI Baby Cry Translator
- Comprehensive baby tracking (feedings, sleep, diaper changes)
- Soothing sounds
- Parent community
- Sustainable two-phone system (less dedicated hardware / e-waste)
- Subscription: $9.99/month or $89.99/year (as announced at Android launch)
Outcomes
- Google Play listing for
com.cappella.appwent live in July 2024. - Founder tagged the engineering team — including Ahsan Islam — on the official Android launch LinkedIn post.
- Fixed-price milestones (bugfix, feature enhancements, baby device, final polish) completed through the engagement.
- Company later wound down after funding ended (founder closed Cappella Dec 2024; listing removed from Play Nov 2024). Still a clean example of shipping on-device audio ML in a consumer parenting app under launch pressure.
References
- Android launch post (founder tags team, including Ahsan Islam) ↗
- Cappella company posts on LinkedIn ↗
- Cappella company page ↗
- Founder shutdown note (Dec 2024) ↗
Product UI imagery from the official Cappella App Store listing (archived Feb 2024); LinkedIn posts cited above for launch narrative and team credit.