You are downloading the Chemistry Aid XAP file v18.104.22.168 for Windows Phone. Chemistry Aid is a free and useful Education app: Windows Phone 8 Chemistry Aid:Molar Mass calculator (w/ Isotopes) and Chemistry reference sheets. The reference sheets include equations, ... You can now download the offline XAP file to install & try it.
Download Locations for Chemistry Aid 22.214.171.124 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 Chemistry Aid XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.