Clown fish

You do not need to apply the frango lens to the whole picture, you can crop out a smaller region to get a specific visual effect.  Here’s what you do:

• tap the screen; you will see the original picture overlaid in a window in the top right of the frango picture,
• long press on the original picture until you see a pair of blue handles defining the cropping rectangle,
• move the blue handles until you have achieved the effect you want,
• don’t forget to save the picture so your crop settings are saved in the history.

In the picture here the original has been cropped to fit neatly into the pentagon lens.