TL;DR: DPoP (pronounced “dee-pop”) stands for Demonstrating Proof of Posession and is an extension to OAuth 2.0. It allows for a server to prove that 2 separate requests came from the same client. This is exactly the key ingredient when you want to keep your secrets safe.
Let’s talk about what DPoP actually is, why it matters, and how it fits into the puzzle of keeping your app secure without needing a backend engineering degree.
If you’ve ever worked on adding a third-party API to a mobile app, you may have had the thought: “Is doing this safe? Is the secret key secure?”
Well, the answer is a resounding: NOPE. But what can you do about this?
The Problem DPoP Solves
OAuth — the very widely used protocol for authentication — was built with the web in mind. It assumes there’s a secure backend server that can keep your tokens safe.
But mobile apps aren’t like that. A mobile app is a client. Once you ship it, it’s in the wild. Anyone can decompile it, inspect its traffic, or extract its secrets. That means any access token you store in your app can be stolen and reused by someone else — even on a different device.
So here’s the problem: Even if your app authenticates properly and gets a legitimate access token, that token isn’t bound to your device. If a hacker steals it, they can use it anywhere.
That’s what DPoP fixes.
What DPoP Does (in plain English)
DPoP stands for “Demonstrating of Proof of Possession.”
Think of it like this: Instead of your app saying, “Here’s my token, trust me,” it now says, “Here’s my token, and here’s cryptographic proof that I’m the one who owns it.”
When your app requests an access token, it also generates a public/private key pair.
- The public key is sent to the authorization server.
- The private key stays on the device.
Then, every time the app makes an API call, it signs the request with that private key. The server can verify the signature using the public key and confirm that:
- The request really came from the same client that got the token.
- The token hasn’t been copied and used elsewhere.
If someone steals the access token, it’s useless without the private key — which never leaves the device.
So, DPoP makes access tokens device-bound. You can read the RFC here: https://datatracker.ietf.org/doc/html/rfc9449
How You’d Implement DPoP (Without Losing Your Mind)
Let’s keep this practical — here’s a high-level look at how you’d use DPoP in a mobile app with a backend API.
Step 1: The app generates a key pair
Your mobile app uses a secure store (like the iOS Keychain or Android Keystore) to generate and save a private key. It then sends the public key to your backend when asking for a token.
Step 2: Your server issues a DPoP-bound token
Your backend (or your identity provider, like Auth0 or your custom OAuth server) ties that public key to the issued access token. That means the token is only valid when accompanied by a signed DPoP proof.
Step 3: The app sends signed requests
For every API call, your app includes a DPoP header — a signed JWT that contains details about the request (like method, URL, and timestamp) and a hash of the access token. The backend verifies the signature against the public key, ensuring it’s the right client.
Step 4: The server validates the proof
If everything checks out — correct signature, fresh timestamp, and matching public key — the request is allowed. Otherwise, it’s rejected.
That’s it. No secrets hard-coded in your app, and stolen tokens become useless.
Why This Matters for Mobile Developers
If you’ve ever said “I’ll just put the API key in the app,” you’re not alone. That’s exactly why Gate/AI exists — to give developers a way to use third-party services safely without setting up a full backend.
DPoP is part of that same philosophy: giving you security that fits the reality of mobile development. It makes OAuth usable in the real world — not just the enterprise diagrams that assume you’ve got a backend team managing gateways and firewalls.
If you want to stop worrying about leaking secrets and just focus on building your app, tools like Gate/AI can help bridge that gap.
In short: DPoP makes sure your access tokens can only be used by the app that got them — not by whoever steals them.
Gate/AI provides a robust implementation of DPoP that is a drop-in integration. No server required! If you’re curious how Gate/AI can help you securely add AI integrations, check it out at https://gate-ai.net.