Never cache user agent(s)
The option is used to prevent cached and optimized pages from being served on certain devices and in certain browsers.
The User-Agent request header is a string that lets servers identify the operating system, vendor, and/or version of the browser that accesses a page.
You can exclude certain User-Agents from being served cache by adding the string value in the Never Cache User Agent(s) text area in the Advanced Rules tab:
User-Agent containing Mobile/15E148 Safari/604.1 string can be added as:
Mobile(.*)Safari(.*)
Exclude a specific browser, as in the example:
(.*)Firefox(.*)
Add a device name, as in the example:
iPad
NexusTablet
Wrong display on tablet
Please see the article for possible solutions:
Wrong display for mobile, tablet or desktop
Additional resources:
Heads up! Some exclusions added here can disable caching for almost all browsers; e.g. (.*)Safari(.*) will match any browser that includes "Safari" in the user agent.