Eight mind-expanding puzzle apps

When you're bored and looking for some basic mental stimulation, puzzle games can help keep your mind sharp while also keeping you entertained. Here are some puzzle games for you to check out, should you get tired of sudoku or if Bejeweled no longer tickles your fancy. The apps are ranked by difficulty, so you should find something that interests you, no matter your skill level.

Quell

With a soothing and beautiful soundtrack, Quell is perhaps one of the more relaxing puzzle games on this list. Like many good puzzle games, Quell is easy to learn but can be difficult to master: You control a water droplet and have to slide around a small area in order to collect pearls. You can only slide in one direction at a time–meaning you can't turn until you've stopped moving–and some levels have spikes that will cause you to pop if you hit them. Like I mentioned earlier, the soundtrack to this game is really well done and I recommend playing it with a good pair of headphones to get the most out of the experience.

Download Quell for Android ($1)

Download Quell for iOS ($2)

Elemental

Elemental is a puzzle game in the same vein as sudoku. However, instead fitting numbers to a grid, you are tasked with creating new elements using water, wind, fire, or earth. Elemental is easy to pick up, even if you aren't particularly skilled at sudoku, and the game offers hints in case you get stuck and don't know what to do next. The game isn't too terribly long, and you could most likely finish it in a single afternoon.

Download Elemental for Android (Free)

Download Elemental for iOS (Free)

Where's My Water?

Made by Disney Interactive, Where's My Water gives you the task of helping Swampy the alligator take a shower. For one reason or another, Swampy lacks plumbing of his own, so you'll have to create pathways to move enough water to Swampy so that he can successfully get clean. The game's cartoonish characters make it great for kids, though even adults will find some challenge in some of the game's later levels. Where's My Water has several expansions that you can purchase once you finish the main game, each with a slightly different twist on the core gameplay.

Download Where's My Water? for Android ($1)

Download Where's My Water? for iOS ($1)

Cryptica

While it may sound like a survival horror game, Cryptica is actually a very engaging puzzle game where you slide around stone blocks to position them on specific points. What makes Cryptica tricky, however, is that sliding one block makes all the other blocks move in that direction as well. The game has 120 levels, each more difficult than the last, and you may find yourself playing certain stages over and over again in an attempt to score a perfect rating.

Download Cryptica for Android ($2)

Monster Flip

Monster Flip, like Where's My Water, is a game that should appeal to people of all ages. The point of the game is to swap monsters so that they form groups of three or more and get cleared from the game board. Every so often a "mad" monster will plop onto the board, and you'll only have a set amount time to remove him before he blows up and causes a game over. Once you think you've mastered the basic game, you can try your hand at the the various other game modes that unlock once you've scored a certain amount of points in Classic mode.

Download Monster Flip for iOS ($1)

Dooors

Dooors has one objective: Open the door in front of you to get to the next room and escape whatever prison currently holds you. Each room is its own puzzle, and you'll need to complete an oddly specific objective before the door will unlock. Some doors will have you performing basic tasks (like sliding something into place), while others will require you to violently shake your phone before they open. The doors get harder to open the further in you go and are sure to stump even the most seasoned puzzler.

Download Dooors for Android (Free)

Download Dooors for iOS (Free)

Cloudy

One of the most difficult puzzle games that I've ever played, Cloudy has you guiding a paper airplane from point A to point B. While that may sound like an easy enough task, you must do this while dodging storm clouds and collecting stars. If you miss even one star, you fail the level and have to start all over again. Though it can be frustrating at times, there is nothing like the feeling of accomplishment that you get when you finally figure out a particularly difficult level.

Download Cloudy for Android (Free)

Puzzle Juice

If you're looking for frantic fun, look no further than Puzzle Juice. This iOS game combines elements from both Tetris and word searches to create a fast paced game that you can play for hours on end. Blocks fall from the top of the screen and slowly begin to fill it up. Creating a row of blocks transforms them into letters which you then have to use to make words to clear up sections of blocks from the screen. The game will test your multitasking abilities as blocks will start to fall faster the longer you play, giving you less time to look for words that can free up some space on screen.

Download Puzzle Juice for iOS ($2)