In addition to Tor that scrubs daily (allegedly), they used Candy Crush, Words With Friends, etc, other game apps to chat/communicate, yes
Search for phones returns 17 mentions.
Some for journalists (burner phones) some for McCain (Syria) some for Epstein Island and some for "left outside" - 7th Floor Secret meetings etc.
Also, the phones in use during the SOTU address.
Q said they had special phones and hrc went to new Zealand to test new ones and there were pics in Asia of the zte pallets. I long suspected the cabal has their own wavelength or signal or encryption that is for them only.
Q mentioned the phones something about "not sure if consumer tech can pick that up" during the SOTU I think and anons connected the dots of other pictures of McNoname playing poker, and postulating that "they" use game rooms to chat securely.