Nokia must subsidise game development for a year or two, as games are not profitable until there is a large installed base of users.

ECONOMIST: Mobile gaming

At the same time, the installed base of Symbian users will continue well after the last Symbian smartphone ships.

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Building reach to engage with a large enough installed base of BB10 active users will take time and requires Blackberry to overcome its branding challenge in the US and Europe.

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Coupland thinks the installed base of about 80 million BlackBerry users will want to upgrade to BB10 devices.

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