Mobile Apps Based on Successful WebApps

Hi all,

As the title states, I plan on creating mobile apps that perform similar functionality as already existing successful web applications (and companies). In that regards, the market has already validated these solutions, given that the companies have produced hundreds of millions in revenue.

My approach is to research their feedback (both good and bad) to determine how to design and deliver a better user experience.

Since these services are often filled with features, I would start simple, attempting to flawlessly execute on 1 feature, and then gradually increase scope based on continual user feedback (and my roadmap).

I'm just wondering if I'm missing anything - it seems too simple. How could a company valued in the millions (or sometimes billions) not find a competent iOS developer to fix their 2/5 star reviewed app? Their users clearly have left poor feedback.

Has anyone attempted this sort of thing? Any insights or words of caution?

Thanks,