Debayan ships
mobile apps that
hold up in the wild.

+34% retention35s → 12sRebuilt the home screen for trial and paid users. Cut time-to-fully-drawn by 66%, removed redundant API calls, and kept frames under 16ms.

100K+ practicesTook a proof-of-concept pitch detector to Practice V2: real-time YIN pitch detection, live pitch graphs, streaks, rubric scoring and teacher review.

5–25ms jitter → 0Replaced SoundPool in the Tabla engine with a sample-accurate PCM mixer on a high-priority scheduler thread. Tabla v2 added dual-zone pitch modelling, per-stroke gain normalization and voice stealing.

Built a suite of music tools: Tabla, Tanpura, Taala, Metronome and Guitar Tuner. The tuner uses a semitone-offset model with hysteresis and per-string sustain windows.

Built live teacher–student tool sync over Agora: tool audio mixed into the call at 48 kHz, plus overlays drawn into outgoing YUV frames before encoding. Several tools can run at once as draggable cards.

Added latency compensation that lines up the backing track, microphone and camera in guided recordings, with diagnostic tools to tune it on each device.

2 weeks+34% teacher retentionLed a team of 3 to ship a new teacher-focused app with assignment review (voice feedback and scoring), progress reports and chat.

Ported web-only features to native Compose: the Perform stage with background audition uploads, an in-call Live Quiz, and Onboarding V3 teacher allocation.

p95 41 → 30 msBuilt a floating glass bottom bar that keeps tabs alive, made the paid dashboard about 2× faster to return to, fixed a recomposition storm, and added device-tier gating for heavy effects.

Built Class Countdown with Android 16 Live Updates: exact alarms, persistence across reboots, and workarounds for ColorOS and OxygenOS.

Built a gamification badges system with gyroscope tilt, a 3D flip reveal and haptics, driven by an API with server-synced unlock state.

+12% trial → paidBuilt a simpler payment onboarding flow for trial users, plus multi-currency and timezone-aware pricing for referrals and wallet.

Built a two-sided referral flow for students and teachers with zero regressions. Replaced Lottie with native Compose animations and shipped it behind Remote Config.

Brought React Native into the native app for Community, published through GitHub Packages, then built a WhatsApp-style chat on top: media, polls, events and link previews.

Built an in-house DevTools module: startup and TTFD benchmarks, burst-request detection, a mock-response editor, a DataStore editor and a deep-link tester.

Moved analytics to remote-configured routing across PostHog, Mixpanel and WebEngage. Removed AppsFlyer and hardware IDs to meet Play Data Safety rules.

Upgraded the toolchain to AGP 9.4, Gradle 9.6, Kotlin 2.3 and compileSdk 37. Added 16 KB page-size support and hardened CI with Firebase App Distribution and Chucker.

Wrote Claude Code skills and architecture-context docs so AI agents follow the codebase’s conventions, plus parity specs that keep the Android, iOS and web audio engines consistent.

Integrated Google Play Billing, Razorpay, PayU and PhonePe with UPI Autopay, recurring payments, free trials and referrals, plus cancel, resume and upgrade flows.

40% faster loadsBuilt server-driven UI from scratch with Paging3 + RemoteMediator for the new Vertical MVP.

Migrated ExoPlayer2 to Media3 with MediaSessionService and MediaController for background playback, next/previous controls and a custom notification.

99.8% crash-freeFixed long-standing Media3 crashes.

Improved the video player with pre-fetching, caching and cursor-based pagination.

Rebuilt the player UI as a sticky mini-player, like YouTube Music and Spotify.

Replaced AppsFlyer with the Singular SDK for marketing attribution.

Added Flipper (about 30% faster dev cycle) and GitHub Actions CI for test distribution.

Built a custom navigation bar and home screen on Paging3 for smooth loading.