Can a paper directly be written on a new application developed rather then an algorithm from existing research results or algorithms?
This is something that I have been doing.  If I understand your question correctly, you are looking at a new product using existing algorithms and techniques. If this is the case, the answer is yes: many journals will welcome this, as I have found.  I have also taken an existing technology, aspects of existing algorithms, based on existing research and developed a brand new technique.

A couple of caveats though:


You will need to make the specific context to which it will be used crystal clear, this must be the focus.
You must give full credit for the prior information and techniques.
You must fully justify why such an altered technique is useful, what are the implications and benefits of such a product.