It works by importing a VPN configuration (profile) to your (iPhone/iPad) device settings.
This configuration will make your device able to establish a connection with one of the Avast VPN servers (there are different locations you can connect to). Once this configuration is installed, you can either manage this connection through the SecureLine app (on iOS 8 ) or through your device settings. The connection will be kept ON whenever it's needed (when there's a network traffic).
This VPN connection works by creating a "tunnel" from your device to the destination (a website, youtube, etc.), which encrypts the messages that are sent through it. So your transferred data will always be secured whenever the VPN connection is ON.
It can also work to access geo-restricted content: If you can't access a website or some other content on the Internet due to restrictions on your country, you can use SecureLine to connect to a server in a different country in which the content is available. It will work as if you were located in that country.
With SecureLine, there are no limitations. You can turn the VPN ON to access any kind of data at any time.
But it's mostly recommended when you're connected to a public WiFi.
I also recommend you to connect using the Optimal Location setting or to use the closest location possible, to avoid problems with high latency to the VPN servers due to the distance between you.
Please note that we offer a trial period for you to test it for 7 days. If you like it, you can then get a monthly or yearly subscription to continue using it.
I hope this is clear.
Let me known if you have any other concerns.
Regards,
Jobert