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What are some of the best tools for editing photos?

I use ,,healing'' the most in order to erase the people or ugly things in the back.

I think it depends on what you need to use tools. When it comes to posting a personal picture on Instagram I don't think you need to choose professional apps or to edit the picture too much. Professional photos on the other hand they need a little bit more photoshop. I am not an expert but when I edit my photos I usually use face retouch, ,,remove'' as well, and sometimes tilt-shift. I use http://imglarger.com to prepare my photos and make them look attractive. I like that it doesn't ruin the quality and it's handy.