Get the app

Prototype · Cal Hacks 13.0

The bag that checks you out.

Drop your groceries in and walk out of the store. Bag It totals everything and the receipt lands on your phone. No checkout line.

Get the appHow it works

Android 8.0+ · 6.6 MB · iPhone: source build only

Illustration of the Bag It smart bag: a fabric tote with a small module on the rim that holds the status light, and two small cameras at the rim corners for the optional vision module.

How it works

Shop like you always do.

  1. 01

    Drop it in

    Put items straight into the bag. It reports each tagged item to your phone, and your list keeps up.

  2. 02

    It knows

    The bag talks to your phone over Bluetooth. Your phone’s location tells the app which store you’re in, so every item gets that store’s price.

  3. 03

    Walk out

    Leave the store and you’re charged automatically (simulated in this prototype). The receipt appears on your phone with a notification, and the bag’s light confirms it.

Inside the bag

Prototype specs.

What the current prototype is built from. Size, weight and power aren’t specified yet.

  1. Rim cameras, for the optional vision module
  2. Module: ESP32 with Bluetooth Low Energy
  3. Status light
Illustration of the prototype.
Controller
ESP32 microcontroller
Connection
Bluetooth Low Energy to your phoneNordic UART service
Item sensing
Tagged items, each tag counted onceThe tag reader is still a prototype input
Vision (optional)
Two rim cameras and a Jetson Nano running YOLOv8n on the device
Status light
Confirms when your bag is paid
Store detection
Your phone’s precise location
Checkout
Automatic when you walk out
Companion app
Android 8.0 or neweriPhone (iOS 16+) as a source build

Get the app

Your bag pairs with your phone.

The companion app is called SmartBag. It shows what’s in your bag and keeps your receipts.

Android

Version 3.0 for Android 8.0 or newer.

Download for Android

APK, 6.6 MB. It isn’t on Google Play yet, so Android will ask you to allow the install. Then allow Bluetooth (Nearby devices), precise location and notifications, open SmartBag near your bag and tap Connect bag.

iPhone

Not on the App Store yet. Developers can build it from source with Xcode 15 for iOS 16 or newer.

Download iPhone source (ZIP, 72 KB)

On a computer?Scan with your Android phone to download the app.

FAQ

Questions.

Am I actually charged?

No. Bag It is a prototype and payments are simulated. No payment details are collected and no money moves; receipts show a demo card.

Which stores work?

Only the demo stores set up for this prototype. Anywhere else, nothing is priced or charged.

What if an item isn’t sold in this store?

It shows as “not sold here” and isn’t charged.

Why does the app need my location?

To know which store you’re in and when you’ve left. Use precise location; approximate isn’t accurate enough. There’s no account: the app uses an anonymous identity. This prototype’s test database is publicly readable.

The app can’t find my bag.

Make sure the bag is powered and nearby. Turn on Bluetooth, allow Nearby devices for SmartBag, then tap Connect bag.