The Pillar review
Whatever you might think about the quality of The Witness, it's a difficult game to recommend simply because its creator has revealed himself--on multiple occasions--to be an outspoken jerk. With that in mind, I'm actually glad to see a game like The Pillar come along. There's no arguing this game hasn't borrowed its conceit whole-cloth from The Witness, but it is just different (and mobile-friendly) enough to feel like a fresh take on a unique puzzle game formula that you can feel much better about playing.
Enigmatic environment
The Pillar is a first-person puzzle game where you wander through environments to find and solve puzzles. Most of said puzzles are in the form of screens that are attached to mysterious obelisks that poke out of the ground, though there are times where you do other things like find and step on switches, move boxes, etc. You know, pretty standard puzzle game stuff.
In terms of story, there is essentially none. It's just you and the world. You don't know why you're there, nor do you really know where "there" is. Solving puzzles and exploring doesn't really provide much insight, either, and there's no dramatic reveals that suddenly make things click into place.
Mobile meandering
All of the screen-based puzzles in The Pillar are some variation on line-drawing puzzles. You'll see a grid, and and you may have to fill in every square by drawing one line, or follow a pattern in a "Simon Says"-style routine. There's only about a half-dozen of these variations and they get recycled across each level. Outside of this, you may be tasked with other environmental manipulation to unlock more of these puzzles, and only after completing all of them can you move on to the next stage of the game.
Unlike something like The Witness, The Pillar isn't a completely open world for you to move between puzzles at your own pace. Each environment is self-contained and follows a set progression of puzzles you need to complete. These constraints may feel limiting, but I found them to be appropriate for a game you might play on-the-go. You don't have to worry about getting lost or forgetting too much about how any mechanics or puzzle types work.
Lost in the wind
This focused design works really well for about 75% of The Pillar, but its later stages get a bit grander in scope, using teleportation and other new mechanics to stretch the puzzle possibilities. Unfortunately, though, I don't think most of the late-game additions really add much to the experience. In fact, the lack of context about the world or what's happening makes a lot of these environmental novelties just feel like tedious extra steps.
There's also some weird quirks to The Pillar that make it a little less mobile-friendly than it appears. Certain puzzles have some procedurally generated solutions that can change between play sessions. There's also no apparent way to pause the game or access settings once you've started playing outside of locking the screen.
The bottom line
Despite a few quirks, I can't think of a better way to enjoy something like The Witness than picking up The Pillar on mobile. It's a bit more manageable of an experience for small screens, the money you spend on it won't be going to a notably problematic person, and it's a pretty solid puzzle game in its own right.