It depends on many factors, including your financial situation, your preferences and your relationship with your significant other.

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There's the nice addition of some metrics between you and your phonebook, visualizing that precarious balance between text messages and calls with your significant other -- or a timegraph of when you call Mom.

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Finding the right partner with whom to embark upon this journey can perhaps be the most important decision you make after all, you may end up spending as much time with this person as you do with as your own spouse or significant other.

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If your significant other is more familiar with your chest than you are, then congratulations on your enviable sex life!

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