REACHit for Cortana was originally unveiled last year, an upgrade to the existing REACHit app. It allows Cortana to search more locations to find files, including cloud storage services like Dropbox, Google Drive, and Box. You can also search other PCs and tablets if they're connected to your REACHit account. And because it's connected with Cortana, you can search all of these places just with your voice. REACHit also uses location data, contacts, and more to narrow down its search.
REACHit for Cortana is currently in beta. The beta is restricted to users based in the U.S. at this time.