I strongly recommend you use something like "CharlesProxy" (or similar). Be aware of 2 things when u setup the proxy (I hope it is an application you are developing, otherwise be sure of what you do cause it can be ILEGAL):
1 - If you want to attack from your Android/iOS phone to the proxy installed in your local computer, you need the proxy to be configured to use the local IP:PORT (which means CharlesProxy needs to be configured as an address as 192.168.x.x if using a normal wifi network). Then, the Android/iOS phone needs to be setting the proxy to the same IP:PORT
2 - If the app uses https, there are several ways to manage HTTPS connections:
a) If your application accepts ALL Certificates, then it is not a problem for whatever proxy to capture and decrypt the information.
b) If your application accepts only system (and trusted) certificates, you have to export the charlesproxy certificate to your Android phone and to add it into the list of user's trusted certificates.
c) If your application is correctly doing "Certificate pinning", you won't be able to capture the traffic, unless you have the private certificate of your server and you add it in both (your phone) and the proxy configuration.
Hope it helps!