Comment by Priotecs

Good questions. - The Android version came about two years after the iOS app. iOS was always my primary focus and the main success driver. - Both apps are 100% native. No cross-platform framework and no web views. It may sound more complex, but for me it was actually simpler and more controllable that way. - There is very little shared code between platforms. Concepts and ideas are shared, but the implementations are platform-specific. - The core app functionality is almost entirely on-device. MoneyControl works locally by design. There is an optional WebApp that adds device sync and a browser-based interface, but the server side is essentially limited to synchronization.

In short: native apps, local-first architecture, with sync as an optional layer rather than a requirement.