dmHexCards

The hexadecimal number system is trickier to handle than other non-decimal systems, such as binary or octal, due to the addition of letters into the mix.
Things get even more complicated if you have to perform operations like addition and multiplication, especially if you want to do them without using a calculator.

Learn and memorize hexadecimal operations using flash cards

dmHexCards is an application that enables you to learn how to perform basic hex calculations without the need for a calculator. It achieves this by using a flash card system which generates random operations for you to calculate. After you reach a solution, you can reveal the answer and check whether you got it right.
The flash cards feature addition and multiplication operations and you can switch between them with ease by clicking on the operator. dmHexCards supports only single digit calculations, which is probably about as far as anyone would be willing to go without using a calculator. So, in essence, the greatest number achievable would be F*F, which is 225.

View the binary and decimal values for every calculation

For every calculation, the application displays the binary and decimal alternatives of the result as well. These can be useful if you are not yet familiar with how hexadecimal numbers work, or if you are interested in learning a bit of binary at the same time. The aforementioned binary values are displayed in an 8-bit variable, although for the numbers A through F only 4 bits are used for convenience.
dmHexCards displays a selection of programming text tips in its interface after every calculation, to offer you something to read while you are learning. These tips are stored in a TXT file in the application's directory and you can change them to feature anything you want by editing the document's contents.

In conclusion

Programmers who deal with hexadecimal numbers and calculations on a daily basis can greatly profit from using dmHexCards, but thanks to the intuitive and easy-to-use interface, anyone can learn the secrets of hex numbers.