You are downloading the Calls+ XAP file v126.96.36.199 for Windows Phone. Calls+ is a free and useful Productivity app: Note: To use this app, please go to Settings on your Windows Phone. This app will NOT appear in your list of installed apps. Call Extras ... You can now download the offline XAP file to install & try it.
Download Locations for Calls+ 188.8.131.52 XAP file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline XAP 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 Calls+ XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.