Sniff is a Cloudflare Worker that returns Google Play app details and download URLs for the stable, beta, and alpha release channels. The details include the version code, changelog, and download size.

Features

• One endpoint returns app details and download URLs for the latest version.
• Beta and alpha channels work for any app whose testing program the channel's account has joined.
• Splits are merged across arm64-v8a, armeabi-v7a, x86, and x86_64 devices, so one call lists every APK split the app ships.

API endpoints

Interactive API reference is served at /v2/docs; the OpenAPI document is available at /v2/openapi.json.

Get latest app details and download info

GET /v2/download/:package_name/:channel

Returns app metadata and download URLs for the latest version available on the requested channel. Google Play only lists the latest version, so no build ID or version code is required in the URL. Metadata and download fields are merged under data; the selected version is in data.item.details.app_details.version_code. All download targets use that version.

Splits are merged across download devices (px_9a/arm64-v8a, sm_a13_5g/armeabi-v7a, google_kiwi_x86_64/x86+x86_64). ABIs whose requests fail are skipped; a partial merge still returns 200.

Parameters:

• package_name: The package identifier of the app (e.g., com.discord)
• channel: Release channel (stable, beta, or alpha)

Possible channels:

• stable - Production release (always available)
• beta - Beta program release (when the BETA_* account has joined the app's testing program)
• alpha - Alpha program release (when the ALPHA_* account has joined the app's testing program)

Response Format:

Successful response (GET /v2/download/com.discord/stable, trimmed):

{
    "success": true,
    "data": {
        "item": {
            "id": "com.discord",
            "sub_id": "com.discord",
            "type": 1,
            "category_id": 3,
            "title": "Discord - Talk, Play, Hang Out",
            "creator": "Discord Inc.",
            "description_html": "Discord is designed for gaming...",
            "offer": [
                {
                    "micros": 0,
                    "currency_code": "EUR",
                    "formatted_amount": "",
                    "checkout_flow_required": false,
                    "offer_type": 1
                }
            ],
            "details": {
                "app_details": {
                    "developer_name": "Discord Inc.",
                    "version_code": 345009,
                    "version_string": "345.9 - Stable",
                    "info_download_size": 159659592,
                    "developer_email": "support@discord.com",
                    "developer_website": "https://dis.gd/contact",
                    "info_download": "500,000,000+ downloads",
                    "package_name": "com.discord",
                    "recent_changes_html": "We've been hard at work...",
                    "info_updated_on": "Sep 11, 2026",
                    "target_sdk_version": 36
                }
            },
            "app_info": {
                "section": [
                    {
                        "label": "In-app purchases",
                        "container": {
                            "description": "€0.84 - €274.99 if billed through Play"
                        }
                    },
                    {
                        "label": "Offered by",
                        "container": {
                            "description": "Google Commerce Ltd"
                        }
                    },
                    {
                        "label": "Released on",
                        "container": {
                            "description": "May 13, 2015"
                        }
                    }
                ]
            },
            "mature": false,
            "promotional_description": "Group Chat That's Fun & Games",
            "available_for_preregistration": false,
            "force_shareability": false
        },
        "footer_html": "All prices include VAT.",
        "enable_reviews": false,
        "main_apk_url": "https://play.googleapis.com/download/by-token/download?token=...",
        "splits": [
            {
                "name": "config.arm64_v8a",
                "download_url": "https://play.googleapis.com/download/by-token/download?token=..."
            },
            {
                "name": "config.en",
                "download_url": "https://play.googleapis.com/download/by-token/download?token=..."
            },
            {
                "name": "config.it",
                "download_url": "https://play.googleapis.com/download/by-token/download?token=..."
            },
            {
                "name": "config.xxhdpi",
                "download_url": "https://play.googleapis.com/download/by-token/download?token=..."
            },
            {
                "name": "config.armeabi_v7a",
                "download_url": "https://play.googleapis.com/download/by-token/download?token=..."
            },
            {
                "name": "config.xhdpi",
                "download_url": "https://play.googleapis.com/download/by-token/download?token=..."
            }
        ],
        "additional_files": [],
        "dex_metadata_url": "https://play.googleapis.com/download/by-token/download?token=..."
    },
    "error": null
}

Error response:

{
    "success": false,
    "data": null,
    "error": "App 'com.discord' not found"
}

Build from source

Prerequisites:

• Rust stable with the wasm32-unknown-unknown target (rustup target add wasm32-unknown-unknown)
• Bun (used to run Wrangler)
• A Cloudflare account for deploy only (not needed for local dev)

git clone https://github.com/madkarmaa/sniff
cd sniff
rustup target add wasm32-unknown-unknown

1. Mint Google Play tokens

Each channel needs a Google account email plus an AAS token. To mint an AAS token from a one-time OAuth token (see gpapi/src/lib.rs docs for how to grab the oauth2_4/ cookie), use the helper:

cargo run -p oauth2aas -- <email> <oauth_token>

It prints the AAS token. Repeat for every account you plan to use.

2. Local dev

Create .dev.vars (gitignored, picked up automatically by wrangler dev):

DEVICE_NAME="px_9a"
STABLE_EMAIL="..."
STABLE_AAS_TOKEN="..."
BETA_EMAIL="..."
BETA_AAS_TOKEN="..."
ALPHA_EMAIL="..."
ALPHA_AAS_TOKEN="..."

STABLE_* is required; beta/alpha pairs are optional and only needed for those channels. Then:

bun install
bun run dev
curl -fsSL -A "Mozilla/5.0" http://localhost:8787/v2/download/com.discord/stable

3. Checks

cargo check --all
cargo fmt --all -- --check
cargo clippy --all -- -D warnings
cargo clippy -p sniff --target wasm32-unknown-unknown -- -D warnings

Environment variables

DEVICE_NAME and the STABLE_* pair are required. The BETA_* and ALPHA_* pairs are only needed to serve those channels.

• DEVICE_NAME: Device identifier for metadata requests (default px_9a in wrangler.toml); download targets remain independent
• STABLE_EMAIL: Email for stable track access
• STABLE_AAS_TOKEN: Authentication token for stable track
• BETA_EMAIL: Email enrolled in beta programs
• BETA_AAS_TOKEN: Authentication token for beta access
• ALPHA_EMAIL: Email enrolled in alpha programs
• ALPHA_AAS_TOKEN: Authentication token for alpha access