Documents on a Microsoft download page reveal that the company might be working on a Touch Cover for the iPad. The page was first spotted by the German site WinFuture.
In documents Microsoft posted in April, an "iPad Touch Cover (Model 1719)" is listed as a device containing lithium batteries, along with the HoloLens, Surface tablets and other products. That could mean it would allow wireless connectivity between an iPad and the Touch Cover, which could act as the keyboard for the tablet.
Microsoft didn't immediately respond to a request for comment.