You are downloading the Threema XAP file v188.8.131.52 for Windows Phone. Threema is a free and useful Social app: Threema is the world’s favorite secure messenger and keeps your data out of the hands of hackers, corporations and governments. Threema can be used ... You can now download the offline XAP file to install & try it.
Download Locations for Threema 184.108.40.206 XAP file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Threema XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.