In Facebook's drive to house more content and provide a better browsing experience, they have launched Facebook Instant. The general idea is to virtually eliminate any load times for content as speed is arguably the number one requirement for success on mobile. The alternative is long load times via browser and high bounce rates/low engagement. Take a look at the difference in story load times compared below.
Whilst this is nothing new and others have deployed solutions within media already, I believe Facebook will be the catalyst to require faster load times from eCommerce sites. Retailers can no longer rely on the mobile browser and must provide a faster experience whether by native app, overlays in other apps or optimized mobile sites.