Brother and sister Olly and Charlotte McIlroy, from Bexleyheath, spent more than £2,000 on four handsets for their family.
The pair were drawn to the 5S Touch ID technology which allows users to unlock their phone with the touch of a finger.
The queue snaked around a packed Regent's Park, with several people carrying tents and energy drinks as they made their way towards the store from 8am.
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