The DxO ONE iOS application has a built-in composition grid and displays the camera’s principal shooting settings (exposure, white balance, and iPhone battery level).

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  To display the grid and settings, swipe down (when the iPhone is positioned horizontally).

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  To hide them, swipe up.

The shooting settings listed at the top of the screen include:

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  Metering mode.

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  Focus mode.

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  White balance settings.

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  iPhone battery level.

Along the bottom of the screen:

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  Exposure indicator.

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  Shutter speed.

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  Aperture.

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  ISO sensitivity.