Native Android tools
Kotlin from day one. Apps that feel native and run smoothly on modest devices.
Native Android studio
Precise Android tools that stay on the phone, not in the cloud
We engineer offline-first Android apps in Kotlin and Jetpack Compose. No trackers, no advertising ID, no hidden behavior after install.
- Android-native
- Offline-first
- No advertising ID
12:30
Streak7
Week
- Android-native
- Kotlin
- Jetpack Compose
- Offline-first
- Accessibility
- Privacy by design
Our deliverables
Full‑cycle Android development, from concept sketches to production releases, with every detail accounted for.
Compose‑based UI
Declarative screens with Material 3, responsive layouts and purposeful motion.
Device‑first storage
Room and DataStore keep data local, so the app works in tunnels and on planes.
Power‑aware performance
We profile start‑up, jank and background work, then monitor Android Vitals after each release.
Built‑in accessibility
TalkBack labels, high contrast and scalable text are integrated from the start.
Release & maintenance
Signed builds, staged Play rollouts and continuous updates as Android evolves.
Trusted toolbox
A concise set of technologies that keep the codebase maintainable.
Kotlin
Kotlin provides concise, null‑safe code that's easy to audit.
Coroutines & Flow
Coroutines & Flow handle async work without callback chaos.
Jetpack Compose
Jetpack Compose creates adaptive UI for phones and tablets.
Room
Room offers a typed local database for offline persistence.
WorkManager
WorkManager schedules reliable background jobs within battery limits.
Hilt
Hilt injects dependencies, keeping modules testable.
Gradle CI/CD
Gradle CI/CD runs repeatable builds and checks on each change.
Play Console
Play Console manages staged rollouts and release metrics.
0trackers in our apps
100%of app data kept on the device
1platform we build for
Our app
Rosette Ratio
Rosette Ratio follows our own blueprint: native, quick to open and silent about your data.
- Operates without network
- Stores everything locally
- Requests only required permissions
- No accounts, no ads, no analytics SDKs
Our guarantees
Four non‑negotiable rules guide every project.
Zero tracking by design
We never embed analytics, ad SDKs or fingerprinting.
On‑device first
All processing and storage stay on the phone.
Battery discipline
Background work is measured and kept within strict limits.
Accessible by default
Interfaces support TalkBack, large text and proper contrast.
0trackers in our apps
0advertising IDs used
100%of app data kept on the device
1platform we build for
Our workflow
Four phases from initial call to ongoing support. Each phase produces a tangible artifact.
Discovery
Define the problem, target users and absolute constraints.
Architecture
Sketch screens, data flow and permission model before any production code.
Build
Write Kotlin, Compose and tests, deliver incremental builds for review.
Release & care
Stage rollout on Play, monitor vitals, apply fixes and update for new Android releases.
One-way data flow: the interface observes state, and the repository owns the data.
Questions, answered
Brief answers about our process.
What does sasinkum.com do?
We design, develop and maintain native Android apps focused on offline operation and privacy.
Which platforms do you support?
Android exclusively. We dive deep into a single platform.
What do you do with user data?
Data remains on the device. We run no analytics, no ad SDKs, and never sell data.
How can I contact you?
Email garance8bouvier@gmail.com or use the contact form on this page.
Do you support apps after release?
Yes. We deliver fixes, adapt to new Android versions and keep dependencies up to date.
Plain terms
What we do
What we never do
Build native Android apps in Kotlin
Sell or share personal data
Store user data locally
Add advertising IDs or tracking SDKs
Explain each permission clearly
Hide behavior behind vague policies
Provide post‑release support
Ship unrequested features
Studio details
sasinkum.com is an Android development studio. Meet the engineers behind our tools.
- Companysasinkum.com
- AddressLINKUMA, 20 CHEMIN DES POSES, 74330 POISY
- Phone+48884647671
- Websitesasinkum.com
Start a conversation
Describe your project. Your email client will open with a pre‑filled message.
Privacy, in short
Our apps collect no personal data, use no advertising ID and contain no third‑party trackers. Everything stays on your device. See the full policy for each app below.
- No personal data collected
- No advertising ID
- Delete the app, delete your data
Privacy policies