Free open source alternative app list of Charles :

Whistle

HTTP, HTTP2, HTTPS, Websocket debugging proxy.

FreeWindowsmacOSLinuxAndroidiOS

ProxyPin

Open source free traffic capture HTTP(S)，Support Windows、Mac、Android、IOS、Linux Full platform system You can use it to intercept, inspect & rewrite HTTP(S) traffic, Support capturing Flutter app traffic, ProxyPin is based on Flutter develop, and the UI is beautiful and easy to use. Features Mobile scan code connection: no need to manually configure WiFi proxy, including configuration synchronization. All terminals can scan codes to connect and forward traffic to each other. Domain name filtering: Only intercept the traffic you need, and do not intercept other traffic to avoid interference with other applications. Search: Search requests according to keywords, response types and other conditions Script: Support writing JavaScript scripts to process requests or responses. Request rewrite: Support redirection, support replacement of request or response message, and can also modify request or response according to the increase. Request blocking: Support blocking requests according to URL, and do not send requests to the server. History: Automatically save the captured traffic data for easy backtracking and viewing. Support HAR format export and import. Others: Favorites, toolbox, common encoding tools, as well as QR codes, regular expressions, etc. Mac will prompt untrusted developers when first opened, you need to go to System Preferences-Security & Privacy-Allow any source. Download： https://github.com/wanghongenpin/proxypin/releases iOS App Store： https://apps.apple.com/app/proxypin/id6450932949 Android Google Play： https://play.google.com/store/apps/details?id=com.network.proxy TG: https://t.me/proxypin_en

FreeWindowsmacOSLinuxAndroidiOS

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