Shin Megami Tensei Dx2: Liberators, currently in closed beta, distills just about everything fans love about the classic series into a mobile-friendly package. You'll find demon summoning and fusion, talking to demons, a gripping story, and even the return of the classic franchise's Press Turn battle system from its PlayStation 2 days here. There's also an augmented reality demon viewer that can bring your summoned pals into the real world for viewing, which doesn't require Google's ARCore toolkit. The game is, as mentioned, in closed beta right now, with no set date just yet for an open beta or full release.
The most striking thing about the game is the beauty of the environments, models and art. This is classic Shin Megami Tensei for the most part, and fans will be pleased. There are even bio pages breaking down the lore behind all of the demons, giving you an inside look and new information on your series favorites. The Press Turn battle system here is exactly like it was in Shin Megami Tensei III: Nocturne, wherein players get one turn icon per party member, and burn up one turn icon for a normal attack or spell, or half of one for a spell or attack that hits an enemy's weak spot. The story concerns a smartphone app that reveals demons in the world, and takes place between two warring factions in modern-day Japan. You're on the side of the Liberators, looking to fight demonic oppression and keep humans safe. Sadly, story battles happen after a few prompts and some dialog in most cases, and after going through most of the first chapter, there were no dungeons to be found. This makes the game somewhat like DigimonLinks in that it caters mostly to existing fans and dilutes the game formula to its absolute core.
The AR demon viewer works quite well, and as for creature comforts, you have a server-based chat client where all the players can gather together and talk about whatever they like, as well as the ability to play with sound volumes for voices, music and sound effects, and thankfully, the option to customize notifications from the game or just turn them off entirely. Since the game is in closed beta form, of course, all of this could be subject to change before the final release. The game has been out in Japan for some time now, so expect a mostly refined experience similar to what's written out here, and few bugs.