Debug an Android app's traffic from a Mac
To see what an Android app sends, you make your Mac the phone's proxy and let it decrypt HTTPS. The idea is the same as debugging a desktop app; the extra work is on the device — getting your certificate trusted at the right level and the proxy pointed at your Mac. Here's the reliable way, and the one shortcut worth taking.
STEP 1
Run the proxy on your Mac
Start elcapture, trust its certificate on first run, and note your Mac's IP on the local network (System Settings → Wi-Fi → Details). This is the address the phone will send traffic to.
STEP 2
Point the phone at your Mac
The plain way: on the phone, open the Wi-Fi network's settings, set a manual proxy to your Mac's IP and elcapture's port. The better way, if the phone is plugged in with USB debugging on, is adb — elcapture can set the proxy and push the certificate over adb for you, which avoids the Wi-Fi fiddling and works even when the networks don't cooperate.
STEP 3
Trust the certificate at the system level
This is the step people miss. Since Android 7, apps ignore user-installed certificates by default and only trust system ones, unless the app explicitly opts in. So a certificate added through the normal Settings screen often won't help. You need it in the system store, which needs a rooted device or an emulator — and that's exactly what elcapture's adb setup installs when the device allows it.
STEP 4
Use the app and watch
Open the app on the phone. Its requests appear in elcapture's list on your Mac — method, host, path, status, timing — and you can click into headers and bodies, filter to the app's domains, set a breakpoint, or replay a call.
If an app shows nothing
It's probably pinning: the app ships its server's certificate and rejects yours regardless of what's trusted. That needs a separate step — see how to bypass SSL pinning, which picks up right where this guide leaves off.