I am going to apply for PR in Canada Express Entry visa. For that I need to choose an NOC code before applying. I have 6 years of experience in software development. I worked as a developer/programmer in my experience. When I checked for the suitable NOC and found out that 2173 and 2174 are very close to my work. I am a bit confused on what to choose. My previous company's relieving letter says " worked as Application Developer". Could anyone let me know which code should I use to apply for the Express Entry and which one has more scope of getting a visa (if the NOC code matters).
There are both closely related. However 2174 also says Computer programmers and interactive media developers . I would say if that doesn't apply to you, you should go ahead with 2173 which is Software engineers and designers.
No the NOC code doesn't increase your chance of getting a permanent residence. However choosing the wrong NOC code may result in rejection of the application.
YMMV but in my opinion any of them should be fine. Check your designation of previous companies and compare it to 2173 and 2174. You want to compare the Main duties section with the letters from the previous companies. Whichever matches closely, you should go with that.