i have seen people to more concerned about the type of work they do. they think system side work is better compared to application side. so i wanted to know the pros and cons of both.
please i didn't find the proper answer anywhere so i am asking here.
Better could mean "More Fun" or "Higher Status" or "Higher Pay" or "Greater Job Security" or many other things.
I have seen situations where the UI construction is outsourced while the core services are seen as mission critical and kept in house. So in that organisation it seems clear what is most valued.
As we get towards UI development the skill sets can shift a bit, the aesthetics and visual skills, concerns for usability start to be more valuable. Folks who work mostly on services and middleware may feel less comfortable in that UI space. Hence if you talk to the server-side guys they might say "More Fun here".
Maybe you could survey the job market and compare salaries of UI developers and server-side developers.
My opinion: there are fundamentally different mind-sets between working in "Application" and "Service". Some individuals feel much more at home in one or the other, and great developers in either have fulfilling careers. Some (but not all) developers seem to be able to seemlessly shift between the mind sets.
There is no universal "better" - for example if you are into UI development, sorry that's "User Experience" now isn't it? If your a UX wizard then you're really not going to enjoy working on development which focuses on things that tend to have very little to do with the front end user.
Development is a very broad church - although the majority of the core skills (fundamentally problem solving and implementing those solutions) are common the specifics vary substanially - games developers require a particular mindset that in places is substantially different to that of a developer doing line of business back office systems.
Within the same web application, front end client work in the browser can be utterly different to that required in the back end model.
Within almost every area there are going to be superstars who earn shedloads of money (this, I suspect, is the mythical "better") but most of us have to put our heads down and get on with it regardless of what area we work in.
Do what you enjoy...