Kids can use this iPad app to help them visualize concepts in fractions, decimals and percentages by making comparisons using virtual manipulatives.  There are pullout trays for fractions, decimals, and percentages.  Use the “i” settings to change to tiles or circles, snap to grid, and hide or show numbers.  There is also a pencil tool so students can write problems, equations and solutions in the space as they manipulate the tiles or circles.

There are no third-party ads with this free app, no data collection tools, or in-app purchases.

From site:  Step 1.) You play the role of a 17th century Caribbean Buccaneer who sails from port to port looking to steal from Spanish treasure ships.

Step 2.) Read the decimal message that appears at the top of the screen. Then, shoot the boat that matches the decimal message (that has the numerical version of the message) with your decimal cannonball by clicking on it. You move from round to round by destroying all of the ships.

Step 3.) After each round you successfully pass, you can obtain a special code that will take you to that round each time you play.

Math-Play.com has several games to reinforce basic concepts in decimals.  Play to practice adding, subtracting, multiplying and dividing decimals, and changing decimals to percentages.

In Decimal Switch you click on arrow to rearrange decimal numbers so they are in ascending order (lowest value to highest value).

Help the boy cross the Bewitched River.  You must complete a path of stones across the river by dragging the ones with the correct fractions or decimals in each spot.  Pick your stones carefully!  There are decoys. 

You have three life jackets to use if you make a mistake.  After three mistakes, you use up your life jackets and have to start all over. 

This game give kids practice with fraction and decimal equivalents and with ordering them in increments from least to greatest.