The reasons behind the move are both ideological and pragmatic. If you ask Mozilla chief Chris Beard, it's a way of "fighting against the rising tide" of walled gardens online. This helps you share web material regardless of the platform you're on, he says. However, it's also a simple matter of growing Mozilla's mobile footprint. Firefox is one of the bigger browsers in the smartphone world, but it's still small relative to Chrome or Safari. Pocket puts Mozilla's brand in front of more people, and might just give them an incentive to try Firefox when they'd otherwise have given it a pass.