You knew it was just a matter of time before Twitter's stickers became advertising vehicles. The social network has just introduced promoted stickers, which help brands get their message out through the same searchable 'visual hashtags' that you might already be slapping on your photos. Pepsi is the first to embrace the concept, and it'll offer 50 of the emoji you've seen on bottles and cans (see above) as stickers across 10 regions.