If you mobile application uses HTTPS/SSL to secure traffic from clients, you need to enable the “Capture HTTPS CONNECTs,” Decrypt HTTPS traffic,” and “Ignore server certificate errors” on the HTTPS tab. To enable the SSL proxy in Charles, you need to do the following:

●         Go to Proxy > SSL Proxying Settings

●         Click add and enter the host name but leave the port empty

●         On your phone, go to charlesproxy.com/getssl and install the certificate

●         Restart Charles

●         Record the API calls

Setting SSL proxy in Charles

Define the Test Plan in JMeter

●         Open JMeter and add the test plan

●         Add the HTTP Request Default: right click on Test Plan Config Element > HTTP Request Default

●         Fill in the server name and the protocol fields

Add config element HTTP Request Defaults and set server name and protocol

●         Add the Thread Group: right click on Test plan > Add > Threads (Users) > Thread Group

●         Add the HTTP Request: right click on Thread Group > Sampler > HTTP Request

●         Now add the API path, which you have identified from Charles by recording requests, in the Path field of the HTTP Request sampler

Add sampler HTTP request and fill the path field by API identified through Charles

●         Add all of the HTTP Requests of scenarios that you identified earlier

Add sampler HTTP requests for all APIs identified through Charles