Best sketching App on the App Store

I am not a professional graphic designer but as an engineer I do a lot of sketching on iPad to convey ideas and designs and find myself jumping from one App to another because there is always a vital item missing in every App. Until I found this one. Paper 53 was close but the inability to import photos for use as background is a serious flaw. Sketches Pro tops all of the Apps that I tried and really stands out in its professional approach, minimalism where needed but not at the expense of versatility. 5 stars !!! Only one request from the creators: please add the ability to change opacity of layers. Best done with a small slider underneath each layer. This is especially important for the base layer. Thank you.

Guy5989 about Tayasui Sketches - Art Drawing