Very easy. Use a VPN!
You can read the reasons why VPNs are so important on public wi-fi connections in an article by Gary Sims at http://www.androidauthority.com/capture-data-open-wi-fi-726356.
I have written about VPN connections a number of times. Read my past articles about VPNs by starting at https://duckduckgo.com/?q=site%3Aprivacyblog.com+vpn&t=hu&ia=web.