Both Cora and POP are a great choice for SEO tools, Cora goes into much more detail and is the number one search engine optimization tool. The depth in which Cora goes to is mind blowing and the results are the reasons why it is the best. POP is a cut down version and can give you quick and easy wins with regards to your on-page SEO. Both will give you decent results with POP being the easiest SEO tool to use out of each of them.Both pieces of software have monthly payment options although POP gives an annual option too.POP has a nice dashboard and user interface displaying all your projects a