Harster13

If this the sort of effect you are trying to achieve, this is how I would do it ?  All done in Designer Windows.
This has been explained before in this thread, but I like pictures 

 
Take a picture (or download one)

 
Draw a rectangle on top

 
Right click on the Rectangle layer and choose, Mask to Below

Note, make sure the document has a Transparent background.

 
Apply a Gaussian blur Effect to the rectangle layer only, not the image. Make sure just the rectangle layer is selected


 
You can adjust the blur radius or the size of the rectangle to get the effect you want. Here placed on a black background.

 
You can use any shape or, as I did below, apply rounded edges to the rectangle.


 
This method is incredibly flexible. If you turn the rectangle into curves, you can use the node tool to mould the shape.
See my subtle  recurving of the bottom edge.

 

The execution of the launch is great.  it really should catch Photoshop/Lightroom users attention for you appear to have the funding to break the monopoly.  Wishing you success!
 
PS:  Please don't become an Adobe! :)

:blink:
In-house Affinity Photo Video Tutorials seems more catered to professionals & Photo Shop users.
Very difficult for amateurs, totally new to photo editing software.
I purchased this 2 weeks back and still not able grasp one single bit of your quick tutorials!
Look forward to some more intuitive/detailed step by step tutorials for biginners.

reglico, thanks for the clarification. I was just worried that I had missed some feature in AD or I needed to reset/reinstall the app to find it. In English it is indeed "Expand Stroke."
 
I rarely use it because it too often creates a large number of unnecessary nodes. Instead, for filling a line with a bitmap, I use the (deceptively named) Fill tool. It works for strokes as well as fills -- on the Context toolbar the first item is "Context:" & that gives you the choice of applying a fill type to the stroke and/or to the fill separately. It is easy to overlook the stroke choice because it always defaults to "Fill."

I find that when I have a bumpy line I select the nodes in the bumps and delete them. Then it's easier to smooth the lines afterwards.
But a real smooth line tool/action/menu would be very welcome!

I thought I would come back to this subject again because more and more I have seen the need for smoothing. I just can't understand why Affinity Designer does not have that ability. Other programs use it with great success. It is very useful when drawing freehand. It takes time to have to alway go back and correct a line. Please reconsider this. I think there are a lot of other people that would like to have the smoothing ability.

It is good news that you will eventually include the B-spline tool in Affinity.  It is the one tool that I use all the time.  Even in smart mode the pen tool is not nearly as good.   All my cat's whiskers are not as smooth. :) :P
 
Apart from a few "missing tools", I am thrilled with Affinity. Thank you all.

Have you tried the Pen Tool in 'Smart Mode'? It's not quite on a par with the B-Spline Tool, but I find that it works pretty well.
 
As for the missing Undo arrow, take a look at the History panel. I think the slider on there is a much better way of providing the same functionality as DP's Undo/Redo stacks.