Kosher Switch 1.2

One phone, two modes. A swipe-down tile (כשר) switches between open mode (a normal phone) and kosher mode (a kosher phone with its own home screen, apps and look). Entering is one tap; leaving needs the code. Works for an adult or a parent preparing a child's phone.

Kosher mode

	Open mode	Kosher mode
Apps	all	only the allowed apps; the rest are suspended (they keep their home-screen spots)
Internet	all apps	only apps marked "Internet" (plus Google's background service they need), through an always-on blocking VPN
Home screen	your normal launcher	kosher home: clock, Hebrew date, widget, 3-app dock, swipe-up glass drawer
Settings	full	kosher Settings only (Wi-Fi, Bluetooth, flashlight, sound, display, look, language)
Locks	none	no installing/uninstalling, accounts, VPN/DNS, tethering, network reset, factory reset from Settings, safe mode, user switching, Bluetooth file sharing
Notifications	all	only allowed apps and core phone services
Survives restart	–	yes (tested)

Built-in apps

• סידור: Ashkenaz, Sefard and Edot HaMizrach; whole prayers as one text with a parts menu, search, a "now" suggestion, and Tehillim (daily, weekly, all 150 chapters). Offline.
• לוח וזמנים: Hebrew date, parsha, holidays, month view, and zmanim from the phone's location.
• פתקים: notes with bold/italic/underline, headings, bullet lists, tap-to-tick checklists, drawings (colors, pen sizes, eraser, undo), pinning and search.
• מזג אוויר (Weather): live weather for the phone's location and saved cities: now, hourly, 10 days, feels-like, humidity, wind, UV, sunrise/sunset. Data from Open-Meteo. It is the only part of Kosher Switch that uses the internet (no browsing is possible), and a parent can turn it off in open mode. Without a location fix it uses the rough location of the connection.
• עוזר (Assistant): understands Hebrew and English commands: calls, messages (opens Messages with the text ready), alarms, timers, notes, opening apps, changing the dock, order, icons, background and dark/light mode. Anything else is answered by an offline AI model (Qwen 2.5 1.5B, via Google MediaPipe) running on the phone. Nothing leaves the phone.

Look

Light / dark / auto, five backgrounds, adjustable glass effect, three icon styles (Kosher, Glass, Original), drag-to-arrange drawer, haptics, Hebrew or English.

Keypad phones (Xiaomi Qin F21 Pro and similar)

Small screens get a tighter home screen (the top part scrolls; the dock always stays on screen). Keys: on the home screen a number, * or # opens the dialer with it, the green key opens the phone, Menu or Up opens the apps, Left/Right/Down pick a dock app, OK opens it. On the code screen the number keys type, Back erases a digit (it only leaves when the code is empty), OK unlocks. The arrows move a gold ring around every screen.

Setup (once; the app's built-in guide explains it step by step)

Kosher Switch must be the phone's device owner. Two ways:

A. QR code, no computer (the phone is reset). Factory reset, tap the first Welcome screen 6 times, scan the QR code on the download page (docs/index.html, published with GitHub Pages). Android downloads the app and makes it device owner by itself.

B. Computer, nothing erased. Remove all accounts (Settings → Accounts), install the app, run adb shell dpm set-device-owner dev.kosherswitch/.KosherAdmin, then add the accounts back.

Then open Kosher Switch: turn on the notification filter (a button takes you there), set the code, choose apps, and optionally download the assistant. The assistant model can also be copied from a computer to /sdcard/Android/data/dev.kosherswitch/files/assistant.task.

Building and updating

JDK 17 and the Android SDK (platform 34).

• Final version: ./gradlew assembleRelease, then (in open mode, with USB debugging on) adb install -r app/build/outputs/apk/release/app-release.apk.
• Both builds are signed with keystore/kosher-switch.keystore. Keep it backed up. Updates must use this key; without it the installed app can't be updated, and as device owner it can only be removed by a factory reset.
• The final version blocks USB debugging while in kosher mode. After leaving kosher mode, turn USB debugging back on (Settings → Developer options) before connecting a computer.
• Debug builds (assembleDebug, install with -t) are test-only and keep USB debugging on.

Known limits

• Factory reset from the recovery menu (hardware buttons) can't be blocked by an app.
• Android shows "This device belongs to your organization" on the lock screen.
• Links inside Waze's own web view aren't blocked.
• Other apps' dark mode follows Samsung's Dark mode button, not the kosher Settings. These are what a custom ROM would solve.

Credits

Prayer texts from Sefaria.org (see app/src/main/assets/texts/SOURCES.md); KosherJava Zmanim (LGPL 2.1); Google MediaPipe (Apache 2.0); Qwen 2.5 (Apache 2.0); Material icon shapes (Apache 2.0).

Publishing

docs/ is a ready download page: index.html (with the setup QR code, generated in the page) and kosher-switch.apk. Push this repository to GitHub and enable Pages from the docs folder. After each release build, copy app/build/outputs/apk/release/app-release.apk to docs/kosher-switch.apk. The QR code's checksum is the SHA-256 of the signing certificate (base64url); it only changes if the signing key changes.