You are downloading the Magic Ruler XAP file v220.127.116.11 for Windows Phone. Magic Ruler is a free and useful Productivity app: Want to measure something in real life? Got your awesome Windows Phone? Got a card from you wallet? You now have a Magic ... You can now download the offline XAP file to install & try it.
Download Locations for Magic Ruler 18.104.22.168 XAP file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Magic Ruler XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.