I needed the up-to-date list of iTunes categories (as of 2017) for a project but didn't find the list as a JSON anywhere. Here I'm sharing the latest categories list that I extracted from iTunes official page. I hope this helps someone.

itunes-category-list.json

{
    "1": {
        "name": "Arts",
        "sub": [
            "Design",
            "Fashion & Beauty",
            "Food",
            "Literature",
            "Performing Arts",
            "Visual Arts"
        ]
    },
    "2": {
        "name": "Business",
        "sub": [
            "Business News",
            "Careers",
            "Investing",
            "Management & Marketing",
            "Shopping"
        ]
    },
    "3": {
      "name": "Comedy",
      "sub": []
    },
    "4": {
        "name": "Education",
        "sub": [
            "Educational Technology",
            "Higher Education",
            "K-12",
            "Language Courses",
            "Training"
        ]
    },
    "5": {
        "name": "Games & Hobbies",
        "sub": [
            "Automotive",
            "Aviation",
            "Hobbies",
            "Other Games",
            "Video Games"
        ]
    },
    "6": {
        "name": "Government & Organizations",
        "sub": [
            "Local",
            "National",
            "Non-Profit",
            "Regional"
        ]
    },
    "7": {
        "name": "Health",
        "sub": [
            "Alternative Health",
            "Fitness & Nutrition",
            "Self-Help",
            "Sexuality"
        ]
    },
    "8": {
        "name": "Kids & Family",
        "sub": []
    },
    "9": {
        "name": "Music",
        "sub": []
    },
    "10": {
        "name": "News & Politics",
        "sub": []
    },
    "11": {
        "name": "Religion & Spirituality",
        "sub": [
            "Buddhism",
            "Christianity",
            "Hinduism",
            "Islam",
            "Judaism",
            "Other",
            "Spirituality"
        ]
    },
    "12": {
        "name": "Science & Medicine",
        "sub": [
            "Medicine",
            "Natural Sciences",
            "Social Sciences"
        ]
    },
    "13": {
        "name": "Society & Culture",
        "sub": [
            "History",
            "Personal Journals",
            "Philosophy",
            "Places & Travel"
        ]
    },
    "14": {
        "name": "Sports & Recreation",
        "sub": [
            "Amateur",
            "College & High School",
            "Outdoor",
            "Professional"
        ]
    },
    "15": {
        "name": "Technology",
        "sub": [
            "Gadgets",
            "Tech News",
            "Podcasting",
            "Software How-To"
        ]
    },
    "16": {
      "name": "TV & Film",
      "sub": []
    }
}

@bertobox Thanks, I have updated the list.