Wildfire is described as 'Interactive, Inc. specializes in developing simple tools that enable companies to engage the fans and followers across multiple social networks' and is an website in the Social & Communications category. There are six alternatives to Wildfire, not only websites but also apps for Facebook, Instagram and Twitter. The best alternative is Gleam. It's not free, so if you're looking for a free alternative, you could try Launch6. Other great sites and apps similar to Wildfire are VYPER (vyper.io) (Paid), GroupHigh (Paid), Agorapulse (Paid) and Promojam (Paid).
VYPER is a marketing tool that helps brands build beautifully designed giveaways, contests & reward programs that leverage viral marketing strategies to acquire emails, followers, engagement, and customers.