Last spring, Facebook (META -0.09%) launched "Home" -- a start-screen app that, in many ways, turned smartphones running Google's (GOOGL -0.30%) Android into Facebook phones. Unfortunately for Facebook, it turned out to be a colossal failure.

Nevertheless, hijacking Google's operating system remains attractive to its competitors: Yahoo! (NASDAQ: YHOO) is said to have something similar in the works. According to Business Insider, Yahoo! will launch its version of Facebook Home in the coming months. If it's successful -- a big assumption -- it could give Yahoo! a leg up over Google.

Facebook swings and misses
If it had been successful, Home could've been a big win for Facebook, and a big loss for Google. Installing Home on an Android smartphone puts Facebook at the center of the phone -- pictures and status updates appear on the lock screen, while the Facebook app dominates the phone's UI. All the other Android-related apps and services are still there, but buried beneath Facebook, accessible through a separate launcher.

Google offers Android for free, supporting it only as a way to keep its Web applications relevant in a world of mobile computing. With Google's services buried beneath Facebook, Home was seen as a threat to Google when it launched -- particularly as Facebook increasingly moves into search.

But Home was not well received. The HTC First, the phone with Facebook Home installed by default, had its price slashed from $99 to $0.99 within one month. Shortly thereafter, the phone was quietly discontinued.

Reviews of Facebook Home on Google's app store, Google Play, are overwhelmingly negative. It has more one-star reviews than anything else, and Facebook's management has admitted that the app's performance has been disappointing.

If Yahoo! succeeds, it will be huge for the company
But despite Facebook's failure, Yahoo! is seemingly preparing to try something similar. Earlier this month, Business Insider reported that the company is partnering with Celltick on a Yahoo! app for Android phones, and at the Consumer Electronics Show, Yahoo! announced that it had acquired Aviate, a start-up company working on an Android start screen app.

When Facebook Home was announced, I pointed out how Yahoo! could benefit from launching something similar. Yahoo! has a number of Web services (mail, sports, weather, finance, Flickr, Tumblr, etc.) but no platform to bring them together. Google uses Chrome and Android to drive engagement; Yahoo! doesn't have either.

Launching a browser or competing mobile operating system could prove difficult or impossible for Yahoo! -- hijacking Android would be an easier way to promote its Web services on mobile devices.

Should Google be concerned?
As with Facebook Home, if Yahoo!'s new product is successful, it could weigh on Google's services. Android smartphone owners with the Yahoo! start screen app installed could run their Web searches through Yahoo! rather than Google, or use a Yahoo! email address instead of Gmail. Meanwhile, Facebook hasn't given up on Home, rolling out a redesigned version of the app last month. As Facebook plans more mobile products, including a Flipboard competitor, Home could eventually emerge as a decent app.

All of this should be worrying for Google, as the open nature of Android leaves it open for these sorts of attempted takeovers. Still, with Facebook Home crashing and burning so spectacularly, these apps may never find widespread success.