The game is a top down space-shooter that focuses on space exploration, similarly to Mass Effect's planet scanning. You jump or navigate to star systems, then move from planet to planet performing scans. If an anomaly is found, you land to investigate with various events and outcomes. There is a bigger plot going on in the background and there is a big-bag to deal with to keep things interesting. During the travels you'll meet aliens, trade, engage in fun combat etc. Overall a fun game that I played pretty much non-stop in my free time for half a week. Only flaw I can think of is the map, which is pretty rudimentary for certain ingame puzzles. You'll have to resort to using paper for them, or googling the answer if you can't be bothered. I wouldn't let that stop me from playing this, as it's enjoyable.
As far as I'm concerned, this is Frictional's best game. The story is very appealing, to me at least, since it's asking questions I've pondered before. The environments are beautiful, though claustrophobic and you will feel a need to explore them out of interest for the plot. Gameplay wise, it's classic Penumbra style stuff, with less physics puzzles and more scripted ones, less jump scares and monster chases and more self reflection and exploration of concepts that can fill you with dread. No loss there for me. In general, a great story, with a good amount of tension, that should please most fans of the previous games and be a warm welcome to new players to Frictional's style of games. A must play.
TLDR: A great story that everyone who likes Adventure games should experience. Has a few minor shortcomings, but they're to be expected for a game of its age. The story is great! The world is beautifully made and I'd definitely love to get even more information on it, which is why I've bought all 3 games and I'm playing them in order. It doesn't get boring at any point and the mysteries aren't... ridiculous... like in many games. What you see is what you get and what you get is enjoyable. April also has quite the way to explain her current situation and her surroundings. The visuals are good enough for a game of that age. Unfortunately there are technical issues but nothing surmountable. The resolution is stuck to 640x480 and it's fullscreen or nothing. Thankfully, the game is alt-tab friendly, so the lack of window mode is not an issue. The backgrounds are prerendered so the quality and clarity thereof is good enough. Also there's no AA to speak of and the dialog boxes ("Are you sure you want to quit" etc, nothing to do with ingame dialogue) are white. Just press Y or N for the dialog and problem solved. The audio is fine. Definitely better than the visuals. The voice acting can be bad at times, as in old cartoon dub bad, meaning average, but most of the time it's fun and of good quality. Just don't expect modern triple-A voice acting. It wasn't possible at the time. The gameplay is good old point and click puzzle adventure. April does a great job explaining what you're looking at and the prerendered backgrounds are clear enough to prevent any need for pixel hunting. Not to mention that the puzzles do not require pixel hunting, or at least I remember none of that. As far as bugs and glitches go, the game only had one, which caused it to crash when getting to the Police Station. It was fixed by replacing a single file with one I found on the forums. All in all, considering when it was made, it's definitely a 5 star game. I'm cutting one because it's 2016.