Starting March 11th, admins will no longer be able to install new FBML tap applications on their Pages, and must instead use iFrames. To facilitate this shift, Page management tool provider Wildfire Interactive has released “iFrames for Pages”, an app that makes it easy to create a Like-gated welcome tab that can show a different image or custom HTML to fans and n0n-fans.

The app will be available for free for the next three months, allowing developers with or without coding skills to create a welcome tab that drives Likes.

Since forming in 2008, Wildfire Interactive’s sweepstakes and promotions tools have helped it become one of the top Facebook marketing service providers. The company took $4 million in funding last April, and has been steadily expanding its service offering to include Twitter and email marketing services as well as social media measurement.

Now the Facebook Preferred Developer Consultant is aiming to onboard new customers who are looking for simple way to navigate the migration from FBML to more code-heavy iFrames. Once the three month trial is up, Wildfire chief executive Victoria Ransom tells us the company may continue to offer the app for free, or roll it into one of the tiers of its Promotion Builder suite that cost either $5 or $25 per campaign and $0.99 or $2.99 a day.

Once an admin installs the iFrames for Pages app on one of their Pages and provides Wildfire with their contact information, they’re brought to the app’s editor. There they can select whether they want to Like-gate their app, and then upload images or paste in HTML code for the different versions shown to those who have or haven’t Liked their Page.

The option to upload static images allows those with no coding experience to build a compelling welcome tab. The HTML option offers richer functionality, such as linking to another Page tab app, which is useful for directing users from the welcome tab to a promotion, Like-gated content, or the core functionality of a Page.

To create a custom name for the welcome tab, admins must go into the Edit Page interface, select the Apps tab from the sidebar navigation menu, and click the “Edit Settings” link in the iFrames for Pages pane. They can then replace the default “Welcome” title with another name. One minor shortcoming of the app is that admins have to manually Unlike their own Page to see how the welcome tab looks to users who haven’t Liked the Page.

By recognizing a need stemming from Facebook’s developer roadmap and creating a smooth, free solution, Wildfire has positioned itself well to absorb Page admins seeking a graceful stopgap to the migration problem.

Strategies for how Pages can most effectively use welcome tabs and the new option to direct Facebook ads to a specific Page landing tab can be found in the Facebook Marketing Bible, Inside Network’s complete guide to marketing and advertising on Facebook.