You are downloading the TKalculator XAP file v188.8.131.52 for Windows Phone. TKalculator is a free and useful Education app: TKalculator™ is a scientific calculator supporting calculations with real and complex numbers, with capabilities to plot 2D and 3D equations, ... You can now download the offline XAP file to install & try it.
Download Locations for TKalculator 184.108.40.206 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 TKalculator XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.