Should I Use Cookie or Token-Based Authentication for My Web and Mobile App?

In PHP, cookie-based auth is mostly about passing a session ID back and forth via HTTPS. You could set up your mobile app to send a similar header that acts like a cookie or session ID, making it compatible with your backend without needing a separate implementation for web and mobile.

Using cookies can keep the token hidden from the client-side code if configured properly with HttpOnly. But if your website is vulnerable to XSS, then it really doesn't matter, as the malicious code can still send requests along with the cookie. Many auth providers use client-accessible storage and seem to manage just fine. So, don’t let laziness dictate your auth choice; consider security first!

When it comes to web applications, a big concern is that third-party JavaScript might access your tokens if they are stored in places like localStorage, which is why httpOnly cookies are preferred. They can't be accessed by front-end scripts, making them more secure against token theft. On the other hand, mobile apps usually operate in a more controlled environment, and using cookies isn't really advantageous there. Mobile apps typically use Authorization headers with bearer tokens, which are sufficient for securing interactions. Just be careful about how you store these tokens on mobile! Using Keychain or Keystore can really boost security, especially with biometric locks for added safety.

While cookies have some security benefits if set up correctly, they also offer practical advantages for web applications. Browsers will automatically include cookies in all requests, which is handy for seamless authentication on page loads. However, for mobile apps, the initial load typically doesn't hit your server, so tokens might offer a more flexible solution depending on the HTTP client you use.