Luckily, one website has already done most of the work for you. It's called APPitic.
The APPitic website is sorted into multiple categories,
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and each category includes resources and apps.
You can even search for apps by subject area:
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This website provides a healthy mix of paid and free applications. While there is a lot of information here, it's organized well and easy to find exactly what you need.
Explore the APPitic website for yourself by clicking HERE.