Privacy Policy

1. Introduction

This Privacy Policy describes how Handoff ("we", "us", or "our") handles information when you use our website, tools, and temporary device-to-device relay service (collectively, the "Service").

Unlike traditional cloud storage or messaging platforms that store your files and communication history indefinitely, Handoff is an ephemeral relay: our systems are engineered to hold your data only for the brief moment required to move it between your paired devices.

2. Information We Process & How It Is Handled

A. Transferred Files

When you select and upload files to send between your paired devices:

• Client-Side Zero-Knowledge Encryption (Files under 100 MB): Files up to 100 MB are automatically encrypted directly in your browser using 256-bit AES-GCM (Web Cryptography API) before being uploaded. The temporary file stored in cloud storage is raw ciphertext. Neither Handoff, Cloudflare, nor any intermediary holds the decryption key or possesses the ability to decrypt your files.
• Direct Encrypted In-Transit Transfers (Files over 100 MB): Files larger than 100 MB (up to 1.5 GB) stream directly to temporary cloud storage via secure presigned URLs over encrypted HTTPS / TLS 1.3 channels without client-side encryption, preventing mobile browser memory crashes while ensuring transport security.
• Files are kept temporarily and solely to enable your receiving device to download them.
• We do not inspect, index, analyze, sell, or share the contents of your files.
• Automated Destruction: All uploaded files are permanently deleted immediately upon download or sharing by the recipient, or when either device ends the session. Otherwise they expire 15 minutes after upload, with scheduled automated cleanup removing expired files.

B. Transferred Text

When you send text snippets between your paired devices:

• End-to-End Encrypted: All text snippets are encrypted client-side using zero-knowledge 256-bit AES-GCM prior to transmission.
• Text is relayed transiently in real time over encrypted WebSockets (Supabase Realtime). Intermediate relays only process encrypted ciphertext payloads.
• Text messages exist only in client memory during active transmission, automatically clear when copied, shared, or after 1 minute of inactivity, and are never written to disk, logged, or stored in any persistent database.

C. No User Accounts or Personal Profiles

You can use Handoff completely anonymously. We do not ask for, collect, or store your name, email address, phone number, username, or password. Rooms are identified only by randomly generated, short-lived room tokens.

D. No Payment Information Collected

Handoff is 100% free to use. We do not require payment, subscriptions, credit cards, or billing accounts, and we do not collect, process, or store financial details.

E. Technical Logs & Operational Data

Like all web services, our servers and infrastructure providers automatically log standard technical HTTP request data (such as IP address, browser User-Agent, request timestamp, and HTTP response codes). IP addresses can be considered personal data under laws such as the GDPR, so we treat these logs accordingly: we do not use them to identify, profile, or track visitors. They are processed strictly for security, rate-limiting, DDoS prevention, debugging network errors, and maintaining operational uptime, based on our legitimate interest in keeping the Service secure and available, and are rotated and deleted on standard short retention schedules.

We also use Cloudflare Analytics to understand aggregate traffic and performance. Depending on the metric, this can include page views, page path and referring source, device and browser type, approximate country, and page-load performance. We use these aggregate measurements only to improve reliability and performance; we do not use them for advertising or to build individual user profiles. Cloudflare states that Web Analytics does not use cookies and that its beacon discards the visitor's IP address at the nearest data center instead of storing it in analytics records.

3. Cookies & Local Storage

We believe in a tracker-free web:

• No Tracking Cookies: We do not use third-party tracking cookies, advertising pixels (such as Meta Pixel or Google Ads tags), or cross-site user fingerprinting.
• Functional Session Storage: We use your browser's native sessionStorage and URL hash fragments solely for essential functionality—specifically, to maintain your active room identifier and ephemeral encryption key in client memory. This data is strictly temporary and is cleared when you end the session or close the tab.

4. Third-Party Infrastructure & Subprocessors

We rely on trusted cloud infrastructure providers to securely run the Service. Each subprocessor is bound by data processing terms and industry-standard security certifications:

5. Data Retention & Automatic Purge Schedule

Our retention model is strictly ephemeral:

• Transferred Files: Each uploaded file automatically deletes immediately upon download or sharing by the recipient, or expires 15 minutes after upload. If the user clicks "End handoff", all session files are deleted immediately. Scheduled automated cleanup permanently removes expired files from temporary storage.
• Transferred Text: 0 seconds. Relayed in-memory only and never persisted to storage. Automatically purged from screen when copied, shared, or after 1 minute of inactivity.
• Room Session: Active during your transfer session and terminated immediately upon clicking "End handoff" or closing the browser tab.
• Anonymous Technical Diagnostics: To proactively resolve technical failures (e.g. WebSocket interruptions or upload failures), anonymous technical error logs (error event type and browser user-agent, free of any file content or personal identity) are automatically purged after 48 hours by our scheduled cleanup task.

6. Data Security Measures

We employ robust, modern technical safeguards to protect data while it passes through our Service:

• Client-Side Zero-Knowledge End-to-End Encryption (E2EE): All text snippets and files up to 100 MB are encrypted and decrypted locally in your browser using 256-bit AES-GCM via the W3C Web Cryptography API. Ephemeral encryption keys are generated on your device and shared exclusively with your paired device through the QR code and URL hash fragment (#key=...). The encryption key is never transmitted to, processed by, or stored on our servers.
• Transport Layer Security (TLS 1.3 / WSS): All data in transit, including larger direct transfers up to 1.5 GB, is encrypted using Transport Layer Security (HTTPS / TLS 1.3) and Secure WebSockets (WSS).
• Namespace Isolation & Cryptographic Unguessability: Uploaded files are partitioned into cryptographically generated 10-character room namespaces with high-entropy randomized object paths (yielding over 3.65 quadrillion room combinations), preventing unauthenticated enumeration or directory traversal.
• Automated Physical Deletion: Deletions execute directly via Cloudflare R2 storage API, ensuring physical removal from cloud storage buckets and prevention of orphaned data.
• No Persistent PII: Because we do not store personal profiles, databases cannot be breached for user passwords, emails, or personal identification records.

7. Your Privacy Rights (GDPR, UK GDPR & CCPA)

Under privacy frameworks including the General Data Protection Regulation (GDPR), UK GDPR, and California Consumer Privacy Act (CCPA/CPRA), individuals have specific rights regarding their personal information:

• Right to Erasure ("Right to be Forgotten"): Because all files are automatically destroyed within 15 minutes (or immediately when you click "End handoff") and text is never written to disk, your transferred data is erased by default without requiring a manual deletion request.
• Right of Access & Portability: We do not maintain accounts, identities, or profiles linking individuals to files. Therefore, we do not hold identifiable personal data that can be retrieved after a room has expired.
• Sale of Personal Information: We do not sell, rent, monetize, or disclose your personal information or content to data brokers or third parties for marketing or advertising purposes.

8. Children's Privacy

The Service is not directed to children under the age of 13 (or 16 in the European Economic Area). We do not knowingly collect personal information from children. If you believe a child has provided personal information through our Service, please contact us so we can immediately purge the relevant data.

9. Changes to this Privacy Policy

We may update this Privacy Policy from time to time to reflect operational, technological, or legal developments. When changes occur, we will update the "Last updated" date at the top of this page. We encourage you to review this policy periodically.

10. Contact Us

If you have questions, concerns, or requests regarding this Privacy Policy or our data protection practices, please contact us:

• Website: handoffdrop.app
• Email: contact@handoffdrop.app