You are downloading the OppolisDemo AppXBundle file v2015.123.1128.1761 for Windows Phone. OppolisDemo is a free and useful Books & Reference app: Oppolis demo of windows ... You can now download the offline AppXBundle file to install & try it.
Download Locations for OppolisDemo 2015.123.1128.1761 AppXBundle file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline AppXBundle File To Install It Any More.
To try to install it manually from an SD card, you should choose one of the server location above to get the offline OppolisDemo AppXBundle file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.