Smart redirection determines if a new visitor to your website is arriving from an external page or an internal page.
If a visitor arrives from an external page then smart redirection will examine your redirection rules to see if the visitors needs to be redirected. If the visitor arrives from an internal page then smart redirection will disable further redirects.
If you're redirecting traffic from your main website to a mobile optimized site then enabling smart redirection is the best option so we make it the default. However, there are some cases where disabling smart redirection makes sense. App campaign landing pages, video streaming, and any linear flow of traffic from page A -> page B -> page C are good cases for disabling smart redirection.
How does Smart Redirection work ?
Smart Redirection looks at the site address (from the site setup), and all redirection URLs then checks them against the referring URL (referring host). If there's a match then this visitor is internal so redirection is disabled. If there's no match then this visitor is external and redirection rules are checked.
Smart redirection can also be selectively disabled by checking the Manual Override option. Manual override is super handy for disabling redirects on specific pages.