Offline Grocery List App for Android with Shared Lists and Pantry Tracking

An offline grocery list app for Android with shared lists and pantry tracking keeps one household shopping list on every member's phone, even with no mobile signal, and tracks what is already at home so staples are not bought twice. A family usually runs its shopping from memory, scattered notes, or one person's phone, so two people buy the same milk while the rice that actually ran out stays forgotten, and a dead zone in a supermarket basement or a village market leaves a cloud-only list unreachable at the exact moment it is needed. Pantry tracking closes the other half of the gap: when rice, oats, or cooking oil fall to a low level at home, the household only finds out mid-recipe or mid-shop. The app answers both gaps together: lists that work fully offline, shared across the household, with a pantry record that turns low stock into a shopping-list item before the next shop.

The interactive demo on this page is a web flow demonstration of the same screens; the delivered build is a native Android app, not the web demo. The demo's seeded list holds 10 items across 4 categories, and its pantry view tracks 6 staples with 3 flagged low.

PantryPal starts on one phone with no account and no connection: the user creates a household list, adds items with quantities and categories, and ticks items off while shopping, with every change saved to the phone's own database the moment it is made. When the household shares the list, each member's phone holds its own copy, and edits made offline are queued as small change records rather than whole-list overwrites. The next time a phone reaches the internet, its queued changes sync to the shared copy, and the merge rule applies: items added on any phone are kept, and for a field edited on two phones, the later edit wins. Pantry staples are tracked the same way, and when a staple's remaining level drops to 25% or less, the app surfaces it as a low-stock item that can be added to the shopping list in one tap.

1. The user creates a household list and adds items with a name, quantity, unit and category (Produce, Dairy & Eggs, Bakery, Pantry Staples).
2. While shopping, the user ticks items off; the progress count updates live and checked items stay visible until the list is cleared.
3. The user records pantry staples (rice, oats, cooking oil, flour, sugar, tea leaves) with a remaining level as a percentage.
4. Any staple at or below 25% remaining is flagged low, and one tap adds it to the shopping list with its usual quantity.
5. The list is shared with household members (up to 6 members, design target); each phone keeps its own copy of the list.
6. When a phone is online, its queued offline changes sync to the shared copy and the merged list downloads; additions from all phones are kept, and the later edit wins on any conflicting field.

Tech stack:

• Kotlin · Android SDK
• Jetpack Compose · Material 3
• Room database · local storage
• WorkManager · background sync
• DataStore · preferences
• MVVM architecture
• Git · Android Studio

PantryPal's strongest capabilities are its offline-first lists, its shared household lists, its pantry tracking, and its one-tap bridge between pantry and shopping list. Lists live on the phone itself, so adding, checking off, and editing items works with no signal at all, and every change is stored locally until the phone is online again. Shared lists let every household member add and check off items on their own phone, with a merge rule that keeps additions from both sides and lets the later edit win on simple fields. Pantry tracking records each staple's remaining level and flags anything at or below a 25% remaining threshold, and a single tap moves a flagged staple onto the shopping list with its usual quantity already filled in. Categories, quantities and units keep each list readable as a real shopping trip, and the no-account start means the app is usable the moment it is installed.

• [Offline-first lists] Every list, item, quantity and checked state is stored in the phone's own database first, so the app works fully with no signal and syncs only when the phone is online again.
• [Shared household lists] Up to 6 members (design target) share one list from their own phones, with a visible activity trail showing who added or checked off each item and when.
• [Offline merge rule] When two members edit offline, additions from both phones are kept and the later edit wins on simple fields such as quantity or checked state, so no one's added item is silently dropped.
• [Pantry tracking with low-stock alerts] Staples carry a remaining level as a percentage; anything at or below the 25% remaining threshold (design target) is flagged low and offered for the shopping list in one tap.
• [Categories, quantities and units] Items carry a category (Produce, Dairy & Eggs, Bakery, Pantry Staples), a quantity and a unit (kg, L, packs, pcs), so the list reads like a real shopping trip rather than a plain note.
• [Check-off progress while shopping] Ticking an item marks it bought and updates a live progress count; checked items stay visible until the list is cleared, so the household can see what is already in the trolley.
• [No-account local storage] The app needs no account to start: all data stays on the device until the user chooses to share or sync a list.

Implemented in the delivered build: all 7 features above. Optional at order time: barcode scanning for adding items. Future scope, not in the delivered build: cloud backup, store price comparison, and recipe-based list suggestions.

• Complete Android app source code (Kotlin, Jetpack Compose)
• Installable APK for testing on an Android phone
• Web flow demo of the list, shared and pantry screens
• Project report PDF (background, offline-first design, sync and merge rules, testing)
• PPT presentation for final review
• Viva Q&A preparation document (offline storage, Room, WorkManager, conflict handling)