You are downloading the EarTrainer AppX file v22.214.171.124 for Windows Phone. EarTrainer is a free and useful Education app: Ear training application that allows you to develop two basic skills for every sound engineer: ability to recognize basic waveforms types at ... You can now download the offline AppX file to install & try it.
Download Locations for EarTrainer 126.96.36.199 AppX file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline AppX 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 EarTrainer AppX file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.