I dont think the army permits transferring confidential information via privately owned phones, or via foreign companies, before. And neither does it now. Note

I dont think the army permits transferring confidential information via privately owned phones, or via foreign companies, before. And neither does it now. Note that we have mandatory military service. Every year thousands of new recruits will perform military service for around half a year. After that, they have to attend three weeks of military service yearly (refresher). This always requires organization; when to arrive in the barracks, equipment to bring, request for leave, corona updates etc. Also coordination at which McDonalds to stop at the freeway. Same for professional army members. They need to communicate somehow, without using super encrypted email or radios (schtichwort "fill guns", super). Military IT is also as you expect (old and cumbersome).