Setting up VPN Client (Android)
First, install strongSwan VPN Client
Second, open the application, and press over menu button, it will show you many options, select in "CA certificates"
Third,over the menu button, import the certificate from your files ,before that you must have the cert file in your cellphone's storage
Come back to the main page in the app,and press "Add VPN profile", fill all the info, dont change the "VPN Type" option, and uncheck in "CA certificate" the "Select automatically" box, it will show a new option "Select CA certificate", press, and in the imported CA certificate, your certificate that you previously have imported, will appear
Finally, press "SAVE", and then the screen will show the main menu, with the profile that you have created, just press over it, and it will connect.