Design + UX
Your app is not like the Apple of apps, why?
A few years back, the internet got all excited by a comparison between the bottom of an iPhone and the most recent at that time Samsung phone. You could clearly see that in the Apple phone each element was completely proportional and placed exactly where you'd expect it. Symmetrical. In the Samsung phone each element was placed where it was easier for the engineers to place it. The whole thing looked poorly designed (even though the front of the phone was quite beautiful). This is the main difference between doing something great and doing something just good enough.
A very similar scenario can be seen with mobile apps and websites. The main difference is that it is a lot harder to even out ports on a complicated hardware device, than it is to make your app interface precise. Right now most apps (even the highly praised, award winning ones) have more of a Samsung vibe than Apple's.
Whether your product will be the Apple, or the Samsung is completely up to you.
The above image is a screenshot of a "great update" of one of the polish banking apps. As you can see the icon is not proportional to the space it occupies, it lacks whitespace and to top it off, it's not aligned properly (vertically). The text inside the text field is also off position.
Just to help with visualisation, we added two examples of how in just a few seconds you can modify it to make it better (without a full redesign to make it great). This is of course just one small part of many inside that app that lacks that final QA step. The interface is like the bottom of that samsung phone. Everything is there, just not quite right.
Do you think your app is the Apple of mobile apps?