When the handset nears the limit set by the user a message appears on screen, and if the limit is reached the data function disables itself for the rest of the 30 day period.

BBC: Counting data cost on mobile phones

By using a PIN code, parents also can turn off the 3D function altogether, or limit the ratings of the games that their kids can play.

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Research shows that exercise can help to maintain physical function late in life and that exercising one's brain can limit the progression of senescence.

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