However, should you decide you want more control over how much a filter is applied to your photo, you can double-tap on the the filter's icon. A slider will be displayed, allowing you to adjust the filter strength or apply the filter's frame to your photo.
Here you can see the Amaro filter applied with accompanying frame.
Lastly, the Tools button allows you to take more control over your photo.
Tapping in the tool icon will reveal a total of 10 different tools. By selecting an icon along the bottom (similar to that of the filter selection process) you can adjust contrast, saturation, brightness, warmth, tilt shift, vignette, sharpen, shadows, highlights, and angle.