RT:可以获取版本号等信息

http://itunes.apple.com/lookup?id=409789998

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      "currency" : "USD",
      "sellerUrl" : "http:\/\/twitter.com\/",
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      "fileSizeBytes" : "3499358",
      "genres" : [
        "Social Networking",
        "Utilities"
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      "languageCodesISO2A" : [
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        "RU",
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        "SV",
        "TH",
        "ZH",
        "TR"
      ],
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      "description" : "Twitter is the best way to connect, express yourself and discover what’s happening.\n\n? Connect with people and your interests to get unfiltered access and unique behind-the-scenes perspectives.\n\n? Express yourself with photos, videos and comments.\n\n? Discover what's happening. Get real-time stories, pictures, videos, conversations, ideas, and inspiration all in your timeline.",
      "bundleId" : "com.twitter.twitter-mac",
      "trackViewUrl" : "https:\/\/itunes.apple.com\/us\/app\/twitter\/id409789998?mt=12&uo=4",
      "version" : "3.1",
      "artistViewUrl" : "https:\/\/itunes.apple.com\/us\/artist\/twitter-inc.\/id296415947?mt=12&uo=4",
      "genreIds" : [
        "12016",
        "12019"
      ],
      "releaseDate" : "2011-01-05T08:00:00Z",
      "wrapperType" : "software",
      "userRatingCountForCurrentVersion" : 49,
      "averageUserRatingForCurrentVersion" : 3.5,
      "trackId" : 409789998,
      "minimumOsVersion" : "10.7",
      "formattedPrice" : "Free",
      "primaryGenreId" : 12016,
      "userRatingCount" : 6046,
      "artistId" : 296415947,
      "artistName" : "Twitter, Inc.",
      "trackContentRating" : "4+",
      "price" : 0,
      "trackCensoredName" : "Twitter",
      "trackName" : "Twitter",
      "kind" : "mac-software",
      "contentAdvisoryRating" : "4+",
      "screenshotUrls" : [
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        "http:\/\/a5.mzstatic.com\/us\/r30\/Purple4\/v4\/a8\/6f\/9d\/a86f9d0d-f1e7-98c7-9153-cace6d277323\/screen800x500.jpeg",
        "http:\/\/a5.mzstatic.com\/us\/r30\/Purple5\/v4\/13\/28\/62\/1328628b-bb08-f8f6-c9f2-727b844496ec\/screen800x500.jpeg"
      ],
      "releaseNotes" : "This update brings new photo features to Twitter for Mac.\n? View and post Tweets with as many as four photos (click each image preview to view the full photo)\n? Share photos privately in Messages\n? More performance improvements and bug fixes",
      "sellerName" : "Twitter, Inc.",
      "averageUserRating" : 3.5,
      "primaryGenreName" : "Social Networking"
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iOS 获取AppStore线上应用信息