While i was working in a company, i was told to develop an application. I want to know if it's possible to sell that application as a product in an open market now that i have left that company. What are the legal implications. Thank you
If you developed something for your employer, it is owned by your employer, not youself.
If you were an independant consultant, you have to read the detailed contract, but unless the company was a complete idiot, all contracts include a clause that says the product is theirs, not yours.
What you are allowed to do, usually, is to re-implement the product, because the ideas and concepts are available to all, just not copy/paste the code.