Great question—this is a critical distinction between what a permission technically allows and what an app claims it will use the permission for. Let’s break this down clearly:

1. What the READ_CONTACTS permission actually enables #

When you grant an app the READ_CONTACTS permission, you’re giving it full access to all contact data stored on your device—including phone numbers, emails, physical addresses, notes, and any other fields saved in your contacts.

Technically speaking, "reading" data in this context means the app can:

• Load the contact data into its own memory
• Copy the data to local storage (like the app’s private folder)
• Transmit the data to remote servers (exactly what you observed in the proxy traffic capture)

There’s no built-in restriction in Android’s permission model that prevents an app from copying or uploading contact data once it has READ_CONTACTS access. The permission only governs access to the data, not how the app uses that data after accessing it.

2. The gap between permission intent and app behavior #

In your example, the app claims it only needs READ_CONTACTS to compare phone numbers against its member list. But as you discovered, it’s actually uploading the full contact list. This highlights a key issue:

• The permission grants the app the ability to copy/transfer contacts
• The app’s stated use case is just a promise from the developer, not enforced by the system

Unless you’re using a privacy-focused Android build with additional restrictions (like strict app sandboxing or data exfiltration controls), the system won’t stop the app from misusing the permission.

3. What this means for you #

To answer your core question directly: Yes, granting READ_CONTACTS permission effectively gives the app the ability to copy your contacts—whether that’s storing them locally or sending them to a server. The only thing stopping misuse is the developer’s adherence to their privacy policy (and your ability to monitor or revoke the permission).

Practical steps to protect your data: #

• Revoke permissions anytime: Go to your device’s Settings > Apps > [App Name] > Permissions, and toggle off Contacts if you don’t trust the app’s behavior.
• Monitor network traffic: Use tools like proxy servers (as you did) to check if the app is sending unexpected data to remote servers.
• Use Android’s privacy features: On Android 13+, you can grant "one-time access" to contacts instead of permanent access, limiting how long the app can read your data.
• Audit app privacy policies: Before granting permissions, check if the policy clearly states how contact data will be used and whether it will be shared with third parties.

内容的提问来源于stack exchange，提问作者jdoe