iPad Screenshots


This app is about visualizing ten’s complements.

About ten's complements:
The "ten's complement" is the number that you must add  to get 10.  For example, the ten's complement of 6 is 4.  And the ten's complement of 3 is 7.

Having a clear visual image of single-digit numbers and their ten's complements is known to be very helpful in doing addition and subtraction. It is also a key step in facilitating mental math.

About us:
Digi-Block provides a method for learning about numbers and operations – addition, subtraction, multiplication, and division. There is a progression of steps. Each step is easy to grasp visually. The magic of math is that after mastering a relatively small number of steps, the learner is able to solve difficult problems! Check out digi-block.com to see what else we have to offer.

What’s New

Version 1.0.3

We squashed some bugs!

Keep sending us your feedback.

Ratings and Reviews

JoeyM1952 ,

Wow, this is the difference between teaching and quizzing

This app really helps teach the complements of 10! My kids can actually see the blocks representing the numbers they're choosing add together. If they choose a number too big or too small, they get to see that!

I've always been a fan of Digi-Block, glad to see they're now making apps :)

Kate23KateKateKateKate ,

Making learning meaningful

This app enabled my pre-school daughter to see combinations of ten intuitively. She is learning number sense in the most ideal way possible — by discovering patterns for herself, rather than memorizing facts. She can explain to me how the numbers build. We have also been extremely impressed with the hands-on product on which this was based.

Laura12345555 ,

Fabulous for actually seeing WHY numbers add up to 10

My kids are having so much fun watching the blocks they choose move and are getting really good at learning the complements of 10—I can tell they are really improving!


Digi-Block, Inc.
37.3 MB
Requires iOS 6.0 or later. Compatible with iPad.
Age Rating
Rated 4+
© 2015 Digi-Block, Inc.


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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