Happy Glass - Design Analysis

A game design analysis for Lion Studios' chart topping mobile physics based puzzle game.

Basic Description

Happy Glass is a free physics based puzzle game by Lion Studios. A developer that has been able to put multiple games on the top charts recently.

Happy Glass has reached the top charts in both stores, peaking at #1 on the Play store’s top free games.

The objective is to guide the water into the glass by drawing lines on the screen. Every one of the 500 levels has a set of obstacles to guide the water through and eventually fill the glass. The player is then given 1–3 stars based on how much they drew (less is better).

New obstacles and game mechanics are introduced to increase level variation and difficulty.

Similar Games

Like many mobile games (fine, all games), Happy Glass takes it’s mechanics from other popular titles.

The drawing mechanic has been done many times before. In fact, Lion Studios has another physics based drawing puzzle game called Love Balls.

A game I played a lot that also falls in the drawing puzzle category is Brain It On! Each level has it’s own objective, but you are still drawing to achieve that goal.

The water mechanic has also been used in many games. Most notably in Disney’s Where’s my water? Where you guide water to help Swampy the alligator take a shower. This game has a removal mechanic instead of additive. Instead of drawing lines, you are removing dirt to help guide the water.

Game Loop

The core game loop in Happy glass is the same as other level based puzzle games.

  1. The player is presented with a puzzle.
  2. The player completes the puzzle.
  3. The player is rewarded. Go to 1.

The gameplay is not infinite, it is based on a series of handmade levels.

One small tidbit I’d like to point out is that clicking start skips the level select screen and jumps straight into the level you are on. This is something I like, because they are just getting me to the game faster.

A metric I like to take a look at is the time between rounds. How fast can you go from winning one round to starting the next? Happy Glass has a quick turnaround at about 5 seconds.

Gameplay Mechanics

There are many, many different mechanics that you must puzzle your way through in Happy Glass. I’m through about the first 200 levels and here is a glimpse of what I’ve seen so far:

Immovable objects

Movable objects

Spinny thing

Hot surfaces (remove water)

Non-drawable area

Multiple glasses

Multiple spouts

Glass direction


A game with 500 levels has enough content to keep players hooked for a while, however, Happy Glass still has some light meta content.

The main meta mechanic is unlocking new skins. Some people might disagree that a simple skin store doesn’t qualify as a metagame, but it’s the closest thing in Happy Glass. You are still playing the core game over and over in order to complete the meta game.

There are different colors for the water, faces for the glass, and pencils for drawing.

There are 15 colors for the water at 1000 coins each.

There are 11 different faces ranging from 150 to 4000 coins.

There are 10 pencils ranging from 150 to 2000 coins.

That is a total of 36 different unlockables costing a total of 43650 coins.

Ideally, I would calculate how long it would take to unlock all of these skins, however, the coins can ONLY be obtained by watching ads or buying coins with real money. There are no coins achieved for completing levels.

To be fair, there are new challenge modes that you can acquire coins from, but the amount of coins is very low, the gameplay lacks longevity, and I’m really just focusing on the main game.


The IAPs in this game include removing ads for $2.99, and purchasing various amounts of coins.

There is a banner ad at the bottom of the screen at all times. Interstitial ads run between levels every 2–3 or so.

There are several rewarded video ads.

  1. On the IAP page, you can watch an ad for 100 coins. This seems to be an infinite use item.
  2. When you finish a level there are multiple things that could happen. If you don’t get 3 stars, you have the option to watch an ad to get that third star.

If you do finish with 3 stars, then you can watch an ad for a random reward. There are multiple chance based reward games in Happy Glass.

3. There is a spin the wheel type game.

4. There is a random prize machine game.

Both will give you a random amount of coins between 25 and 250. You can also earn light bulbs which are used for in game hints.

5. Occasionally when you finish a level, you can watch an ad to get one of the expensive skins for free. Wow! That’s a 2000 coin value! Just for ONE ad?? /s

Of course, the random games are probably weighted so that you are more likely to get the lower prizes than the big jackpots.

There could also be some unknown conditions that trigger the free skin prize. A theory of mine is that they give this option to you if you have resisted the other rewarded ads. But it could also just be a 1/10 kind of thing.

I would love to find out, but I’m not going to watch a bunch of ads to figure out the prize probability.

Game Length

The game’s length comes down to how long it takes you to finish all 500 levels and if you want to get all 3 stars or not.

I ran 2 tests timing how long it took me to play 10 levels. Test #1 took 5 minutes, or 30 seconds per level. I did not get stuck on any levels.

Test #2 took 10 minutes, or 1 minute per level. This time around I did get stuck on a couple levels.

I’m going to take the average here and extrapolate to come up with a very rough estimate for how long it would take to complete the game.

7.5 min (for 10 games) * 50 (to equal 500 levels) = 375 minutes or 6.25 hours.

Considering I only play any given mobile game for 5–10 minutes at a time, this game will last me a while (assuming I don’t get bored first).

I don’t factor the skins in the length because I don’t have the average coin output per ad watched.

Game Juice

I like to take a look at the game’s ‘juice’, also referred to as game feel or game responsiveness.

These are things like animations and sound effects that occur when the player interacts with the game in a certain way that makes the game ‘feel’ good.

Happy Glass covers the basics like button movement when you tap and coins physically moving to your counter.

Juice that is unique to Happy Glass is that the pencil waves back and forth when you are drawing.

Another cool piece of juice is that the face changes depending on how much water is inside of it. No water produces a frowny face, some water produces an ‘O’ face, and a filled glass produces… wait for it…. a HAPPY face.


Happy Glass merges the drawing and water mechanics in a simple yet fun puzzle game. The shear amount of levels keep this game playable for hours.

I would have liked to see an in game way to get coins. Achieving the skins ONLY through ads or IAPs rubs me the wrong way. However, since they are only skins, it’s something I can live with.

You can download Happy Glass for free on iOS and Android today.

More design analysis at

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