It is essential to have this in-app, not going to another app. Most people do not realize that even famous images that have no digital magic applied where heavily edited for exposure to support composition.<p>See e.g. 
<a href="http:&#x2F;&#x2F;petapixel.com&#x2F;2013&#x2F;09&#x2F;12&#x2F;marked-photographs-show-iconic-prints-edited-darkroom&#x2F;" rel="nofollow">http:&#x2F;&#x2F;petapixel.com&#x2F;2013&#x2F;09&#x2F;12&#x2F;marked-photographs-show-icon...</a>