Having worked in IT for most of my life, it takes something rather special to impress me technologically, but this Nexus 7 gadget is stunning.  I’ve never been a fan of computer games, preferring real puzzles that you can accidentally drop, but I have now realised that there are some excellent brain games available for computers, often ideas that couldn’t be realised as physical puzzles. If you have a phone or tablet that runs the Android operating system I recommend some of my favourites here, all available from the Google Shop:

Rush Hour - The classic Nob Yoshigahara sliding car puzzle. Your goal is simple: get the Red Car out the Exit Gate by moving the Blocking Cars and Trucks out of the way. The puzzle features 35 brand new challenges and adds bonus features including Hints and Auto-Solve! Plus, players are challenged to solve the puzzle in the fewest possible moves, a serious mental workout! Rush Hour was awarded a 2010 Parents' Choice Gold Award for excellence in mobile play.

Unblock Me - Rush Hour clone. 

Flow Free - Connect matching colors with pipes to create a flow. Pair all colors, and cover the entire board to solve each puzzle in Flow Free. But watch out, pipes will break if they cross or overlap!

Cohesion - This is totally addictive and I can’t think that it could ever be played other than on a computer.  The squares in Cohesion are various colours. If two squares the same colour touch sides, they bond together. The bond is permanent, and the new shape it creates adds to the unique challenge of Cohesion. The puzzle is solved when all the squares of each colour have combined.

Move It Free - Tired of sliding blocks puzzles that only allow block movement in one direction? Then this is for you!  Move it! FREE is a fresh and exciting new block-sliding puzzle, not just an Unblock Me clone!  Also features non-rectangular pieces.

Vexed Pro - similar to Cohesion, but the unit blocks rely on gravity. One of my favourites.

Jungle Block - Rush Hour Safari clone

Sokodroid - Sokoban, the best thing you can do with a computer.

Sliding Puzzle - Traditional 5x4 sliding puzzles.  The physical version of this is one of my Desert Island Puzzles

Godroid and Go Free - Two very good Go programs, I’m still assessing which I prefer.

Monty Hall - a great simulator to help you understand this classic paradox.

Cut The Rope - I’m probably the last to discover this gem. A network of ropes suspend various objects. Cut the ropes strategically to drop the objects into a waiting mouth.

100 Doors - I’m probably also the last to discover this gem and others of its ilk.  Try to discover how to open an almost endless stream of secret-opening doors.  Strangely, I’ve never quite seen the point of secret-opening mechanical puzzles, as once you’ve done them, well, that’s it. Here, there are so many, then you can try 100 Crypts, the Christmas 100 Chimneys and many more.

Untangle - drag the strings to untangle the network of confusion.

Salesman Challenge and also Travelling Salesman - Welcome to the world of a traveling salesman. Your challenge is to create a route trough all cities and return back home. To win the challenge you have to find the shortest route possible.  This is an exploration of an as yet still unsolved paradox.

Modern Proverbs - I was unaware of hidden object puzzles until now. This was the first I found.  My only criticism is that it doesn’t save the game and you will have to start again each time.  There are many other alternatives though.  2 games in one: "Modern Proverbs" with medieval artist Pieter Bruegel's "Netherlandish Proverbs" painting with a modern twist, and "Pieter's Pictures" hidden object game. Instead of outdated proverbs, the painting has been altered (keeping Bruegel's own art) to include such modern words of wisdom as "There's no use crying over spilled milk" and "If you can't stand the heat, get out of the kitchen." Read the item at the top, find and touch it in the picture below and move onto the next item.

www.flickr.com