App Profile: Proxygen

Proxygen is a professional HTTP proxy tool for testing apps and debugging remote API endpoints right on your iPhone, iPad and Mac. And it’s built to delight you while doing it.

The magic lies in a little custom HTTP proxy that the iOS app runs in a local VPN extension. This proxy was developed using SwiftNIO, a framework for blazing fast asynchronous network applications. The proxy can perform TLS Manipulator in the Middle (MitM) to see inside HTTPS connections and apply custom logic to each message.

To put it bluntly, you’ve probably never seen a HTTP proxy this fast before. And you likely won’t notice that your web browsing is even proxied at all.

Features
• High performance SwiftNIO HTTP proxy
• iOS system proxying using a VPN configuration
• Decrypt HTTPS using TLS MitM
• Message history with powerful filtering
• WebSocket message capture
• Syntax highlighting HTTP message editor
• Match to request protocol, method, host and URI
• Replace HTTP headers and body data
• Map to local responses without a remote API
• Drop matched requests and responses
• Store message history and editors in project files

SYNTAX AWARE EDITOR
Edit requests from the message history or create new to any target. All previously sent requests are kept in the project file so you can return to your work later. The editor is based on open source Runestone framework, which uses Tree-sitter for fast language parsing and syntax highlighting. It handles decoding of HTTP content automatically, letting you focus on testing the remote API.

MATCH AND REPLACE
Proxygen can modify requests and responses, on the fly, according to your custom rules. Multiple rules can be combined to create powerful automations that drop traffic to certain destinations, add or remove HTTP headers and respond locally with custom data, bypassing the remote server.

COLUMN VIEW
Proxygen was designed for iPad from the start and offers a one of a kind tablet experience. The app uses an innovative side scrolling list with sortable columns, which makes it possible to work with large message logs with ease. Proxygen on the iPad app comes with full keyboard support with shortcuts for common actions.

PRIVACY
Proxygen contains no third party frameworks for crash reporting or analytics. Note that Proxygen is a TLS MitM proxy, which means that it sees HTTPS network traffic in plain text. This data is transferred from the proxy to the Proxygen app and stored as part of the project document. Make sure you handle the documents accordingly, as they may contain sensitive data such as session tokens and login credentials.

Privacy policy
https://freshbits.fi/apps/proxygen/privacy/

Terms of Use
https://freshbits.fi/apps/proxygen/terms/

Device Mockup created from https://deviceframes.com/templates/iphone-13