If you see https, the session between the web server and the browser on the mobile device you are using is encrypted. You can easily identify web servers that have https configured by looking at the Uniform Resource Locator (URL) in the web address bar of your browser.
Hypertext Transfer Protocol Secure (https) is a combination of the Hypertext Transfer Protocol (HTTP) with the Secure Socket Layer (SSL)/Transport Layer Security (TLS) protocol. TLS is an authentication and security protocol widely implemented in browsers and Web servers. SSL works by using a public key to encrypt data transferred over the SSL connection. Most Web browsers support SSL. It allows you to communicate securely with the web server.