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Swap RGB

Official Description

It is very easy to mix or swap image's red / green / blue channel to make amazing effects owned yourself.
This app won't cause any loss of quality.
Works as the Photos extension and the standalone app.

How to it works:
1. Drag an image in
2. Drag sliders to change percent of mixing red / green / blue channel each other.
3. Save

The iOS version is also available now.