ISLANDERS is a casual city-building game developed by Grizzly Games, Coatsink, and Stage Clear Studios while being published by Coatsink.

Gameplay
Islanders is all about scoring points by strategically placing buildings on your procedurally generated islands to achieve highest score you can. It's pretty simple!
Every new session you get a random island with option of selecting a starting building pack, each providing thematically similar buildings in limited numbers. Use these to obtain enough points to be able to collect another building pack, place these, rinse and repeat until you gather sufficient amount of points to move onto next random island!

To obtain points you select a building from inventory and place it on the map, in this case island. Each building has certain sphere surrounding it, showing off the distance at which it will earn or lose points from existing buildings or other environmental structures. Every building has structures that are compatible and give it extra points when in the sphere, and incompatible, losing points when placed near them. To make it easier on math side, game shows you potential points you can get when placing a building on selected area but before actually putting it, as placing anything on the map means it will remain there permanently. Careful placement and forward planning are important to maximize the score you get!
Once you obtained enough points, you can travel to next randomly generated island and start building it up from the scratch.

Game is over if you have placed all buildings you had in your inventory and didn't collect enough points for another pack to get more structures, or if you don't have enough points to progress onto next island. Then it's back to the start! Worth mentioning you cannot reload the game as every placement you make automatically saves your game and there is no way to revert back to previous states.

Playtime, replayability and other modes
Impossible to determine how long your playtime will be. Can be 5 minutes, can be 50 hours.

Game is set on constant attempts at getting highest score so I would say that does count as replayability.

Islanders has second mode called "Sandbox Mode" where you get to roughly select how your dream island should look like to afterwards build it up anyway and with anything you desire. Name of a mode checks out!

Impressions
Islanders is a tricky little beast. It's a really good game however due to its nature, it takes certain conditions and mindset to fully enjoy it. Otherwise you might end up in a uphill-downhill scenario on "enjoyment scale" like I did, which is described down below.

I can safely say that first impressions were great. Something that is a massive positive from the start is audiovisual side of the game, low-poly minimalistic artstyle with vibrant colour palette looks fantastic, very pleasing for an eye. And you mix that with relaxing soundtrack that you can enjoy or just turn off and play some of your favourite songs or podcasts perhaps, depending on you. Audiovisual aspect never got old for me and by far was my favourite part of the game.

Islanders is quite unique in the city-builder genre. There is no resource gathering, traffic management, technology research, no sidequests or optional objectives. You have a building, you place it, you get the points. Repeat the process until you are done with a session or lose and start all over again. Safe to say simplicity and minimalism it offers is not for everyone. Those who seek more variety, to simply put it, will get bored. Game balances between relaxing atmosphere and strategical approach to building placement quite well, while randomness coming from what structures you get and on what island you will place them adds necessary element to spice things up!
First hours were enjoyable yet painful and very "game-over", as I was learning mechanics and buildings, while top of enjoyment hill came roughly at 15-20 hours mark. At that time I discovered all buildings and learned basics on how to optimize my runs for more points!

Unfortunately afterwards is where it went into downhill territory for me and where my whole issue with recommendation chimes in. Past those 20ish hours game starts to fall off. With nothing new to discover and basics of strategy played out, game wears out and starts, or at least started for me, to be boring, with its key aspect of simplicity turning into double-edged sword. You place same buildings as before in roughly same learned patterns/configurations for maximum points. You start to yearn for something different to do, as randomness of game wears off, especially if you play Islanders in longer sessions.

Something that turned out to be a negative for me is layout of islands. It's always a single island while game could utilize multiple, smaller sized islands for ultimate challenges, with player needing to piece around a whole archipelago of medium/small sized land for you to connect around. Plus game doesn't have that many layouts surprisingly, in my playtime I encountered same islands even 3 or 4 times but simply with different colour palette and very minor changes, extra tree or rock here or there.
Also was not a fan of island transitioning. Points collected on previous island don't stack up. No matter if you get 10 or 10000 points on an island, when you move to next island your start is always same, you don't get any extra packs or "easier" start for all the points grind, only higher score for leaderboard. Which, goes without saying, is riddled with cheaters anyway so.

To make that whole gibberish I wrote make sense: Islanders is good, but to fully enjoy it you should treat it as a smaller sidegame in between big titles. Something to play for 30-40 minutes as a way to relax, either with some of your favourite tunes or with chilling soundtrack game offers.
You should not do what I did, which is grinding it for hour or even slightly longer daily and without playing anything else to break the routine. I assume that is a main reason why my personal experience later on was just...boring, mediocre, even if I had fun in those 20 hours but that is still...less than half of my actual playtime. Game itself can be a nice gateway into more city-builder titles which have more mechanics in them.

Final words and conclusion
If you will enjoy this game you might be interested in a news that a sequel was recently announced! (As of when I'm posting this review.) It seems to be improving some aspects I was complaining about so I might have to check it out in the future...

Relaxing audio, beautiful visuals and minimalism provided in gameplay makes ISLANDERS a great choice for short, casual city-building sessions, but long runs can break the cozy feel it provides.

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