Apple's App Store is nearing its 50 billionth download, so, to celebrate, Apple will be giving away a hefty prize to the lucky person who downloads that milestone app.

On Thursday, Apple began its countdown to the 50 billionth app, which is rapidly ticking away over on the company's website. Should you download the 50 billionth app, you could win an App Store Gift Card worth $10,000 (£6,430).

Download one of the first 50 apps after the milestone has been reached and you could win a $500 App Store Gift Card.

Alongside the countdown, Apple has also published lists of the most popular apps in the history of the App Store. We're sharing the top five in the paid and free categories for both iPad and iPhone below. For the full lists, visit Apple's App Store.

Top all-time paid iPhone apps:

  1. WhatsApp Messenger
  2. Angry Birds
  3. Doodle Jump
  4. Fruit Ninja
  5. Cut the Rope

Top all-time free iPhone apps

  1. Facebook
  2. Skype
  3. eBay
  4. YouTube
  5. Twitter

Top all-time paid iPad apps

  1. Pages
  2. Angry Birds HD
  3. Scrabble for iPad
  4. Garageband
  5. Monopoly for iPad

Top all-time free iPad apps

  1. BBC iPlayer
  2. Skype for iPad
  3. iTV player
  4. eBay for iPad
  5. 4OD

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