The hard part was never the code, and it's certainly not the code now. The hard part is that people download an app once, don't find a reason to open it again, and it quietly dies on the third screen of their phone.
Apps are valued on how many people use them daily or monthly, not on how many features they have. So the question we start with isn't “what should it do” — it's “what makes someone open this tomorrow”. Everything else follows from the answer.
Which is also why we'll sometimes tell you not to build an app. If the job can be done by a good mobile site, an app adds a download, a store review and a permanent maintenance bill for no extra benefit. That's a cheaper conversation to have now than in month six.