The mystery Visual Novel, Root Letter is available globally for PS Vita, PS4, PC (via STEAM), and Smartphones. We actually have covered a review for the first installment of the game—wait, the ‘first’?
Yes, the ‘first’, because Kadokawa Games has announced another Root Letter VNs! Root Letter: Last Answer and Root Letter 2!! The former already has a teaser trailer, and seems like it will be an FMV; games that use pre-recorded video files—a live-action. So there will be actors, just like 428: Shibuya Scramble.
Below is Root Letter: Last Answer teaser trailer. There are no sign for Root Letter 2 trailer, that is, if the it really will be called Root Letter 2. The consoles are still a mystery too.