Microsoft confirmed this weekend that it has delayed — if not killed entirely — a tool designed to make it easy for Android apps to run on Windows 10 phones and tablets.

Dubbed Project Astoria, the effort was unveiled in April as part of an aggressive but risky plan to get developers who write for Android, iOS or the Web to bring their programs to Windows. Developers had begun to raise questions, though, as the tool was never released publicly and Microsoft had stopped talking about it.

Microsoft confirmed to Re/code this weekend that it was not moving ahead with Astoria as planned, but a representative declined to say whether Astoria was delayed, on hold or being scrapped altogether.

“The Astoria bridge is not ready yet, but other tools offer great options for developers,” Microsoft said in a statement, adding that the tools for Web and iOS developers are ready, with another option coming soon to allow older Windows programs to run on phones and tablets. Microsoft said, “We’re committed to offering developers many options to bring their apps to the Windows Platform.”

The Android tool was seen as the riskiest of the four bridges as it amounted to essentially porting over apps written for Android without really taking advantage of Windows itself. BlackBerry employed a similar strategy, allowing Android apps to run on BlackBerry 10 devices via Amazon’s app store. In the end, that proved largely unsatisfying and the company opted to build the Priv, a true Android-based smartphone.

Microsoft’s options for iOS and Web developers require more work on the part of app creators, but they also end up with something that was more of a true Windows app versus just an Android hand-me-down.

With the demise or delay of Astoria, the stakes are even higher for Microsoft to convince mobile developers to put some effort into making a Windows version of their apps. While Microsoft has struggled to lure mobile developers because of Windows’ low share of the phone market, it has a bit more compelling story with Windows 10, where developers can write a universal application that can run on Windows-based phones, tablets, PCs and even on the Xbox game console.

The company has also set a bold goal of having Windows 10 on a billion devices within three years of release and is relying on sheer numbers to eventually win over skeptical developers. In the past, the company tried to attract developers through financial and other incentives, but in some cases developers stopped updating or abandoned their Windows Phone efforts.

“Now we are just very focused,” Windows boss Terry Myerson said in an interview last month. “Let’s get that developer engagement naturally through users and innovation.”