How to debug apps on your handset

Apps on your handset, are essentially clients which communicate with their servers in the remote data center to function. While there are some apps which could work well without network connection, the number is quite rare.

So I am always interested to know what the apps are doing in the background when I tap them, except the start screen and main screen. What IPs are they connecting to, what requests are they initiating, and what data are they sending.

This is especially useful when I am trying to hack an app. I really hate those apps which scan my handset and upload the result in the background or busy downloading and showing ads which will certainly drain the battery.

If you like to do the same thing, you may need packet capturing apps, that could be of great help. Here are two apps you will find helpful.


Thor is designed specifically to debug both http and https traffic on iOS devices. However it’s not a freeware and the price is on the increase constantly.

In order to debug the traffic, the app will create a VPN and route all traffic generated by all your apps. Then you will be able to view hundreds of thousands of requests, these connection data can also be imported to other apps. If you are searching for a specific domain or keyword, no problem, it will let you filter any data.

Packet capture

This is a traffic debug app for Android, a much simplified version compared to Thor.

Like Thor, the app will create a VPN as well (so no root required) to record and analyze the requests. In general, you will see information like app icon and name, server IP and ports the app is connecting to, protocol type (TCP or UDP), date, time and data. Take a look at below screenshot to get a more detailed idea. Since this app do not provide filter functions, I would strongly suggest that you only open the apps you want to debug at a time.

If you know other apps, please share with me on Facebook, I will be glad to hear from you.