[XorNot]

A radio on a soldier is already a dangerous communications device - with a radio you can call in artillery strikes, for example.

There's no particular need IMO to secure smartphones on the battlefield in anyway beyond standard counter-measures - i.e. encrypt the storage, use a passcode unlock.

[codethief]

The Russian military would beg to differ, see the sibling's comment: https://news.ycombinator.com/item?id=43106162

[XorNot]

That's referring to people literally posting selfies online (with the result of giving away their location by either metadata or geo-guessing).

Which is a process and procedure issue, more then a security issue on the phones themselves (except in so far as it's really obvious there's a solid need for an OS for a battlefield device which strips all that stuff out by default).

[mmooss]

Smartphones store data; radios (depending on the radio) do not. The Russian military likely has tools for bypassing typical security.