You are downloading the Prototype Player AppX file v18.104.22.168 for Windows Phone. Prototype Player is a free and useful Productivity app: The Prototype Player app allows customers of medialesson to tun interactive web based app prototypes by entering their customer and project ids. ... You can now download the offline AppX file to install & try it.
Download Locations for Prototype Player 22.214.171.124 AppX file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Prototype Player AppX file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.