Tzachi (צח"י) Application

The Tzachi app serves as a centralized digital platform for community organization and engagement. It required integrating complex external APIs to calculate date-specific content (zmanim) and deploying it fully to production on the Google Play Store.

This is the project that went the full distance — from an empty repository to a signed release on Google Play, with everything that implies about store listings, privacy and data-safety declarations, targetSdk compliance, versioning and staged rollout. Those are the parts of Android development that never appear in a tutorial, and they continue after launch as policy requirements change.

The technically interesting part is that most of the content is not static. Zmanim — the day-dependent times that structure the community schedule — are derived from external data keyed to both the current date and the device location, so the same screen shows something different tomorrow, and different again in another city. The time logic was isolated into a dedicated component so it could be reasoned about and corrected in one place, and so it stays correct when the user travels, when the clock crosses midnight, and across daylight-saving boundaries — exactly the cases where naive implementations silently show yesterday.

Because the app also carries announcements and emergency messaging, degraded network conditions were treated as a normal operating state rather than an error path. Responses are persisted as they arrive and the UI renders from that store rather than from the request, so a failed refresh degrades to slightly older content with a visible indicator instead of an empty screen — which matters most in the very situations where this app gets opened.

The interface is Hebrew and right-to-left end to end, not a mirrored afterthought: layout direction, iconography, numerals and mixed-direction strings were each handled explicitly so Hebrew text with embedded Latin or numeric fragments renders in the correct order for an audience with a wide range of technical comfort.