Creating an app is addicting. Brainstorming the idea with friends is invigorating. Crafting a mood board, the UI, the UX is fun. Architecting it to work cross-platform is a welcome challenge. Inventing solutions to tackle problems is satisfying. All of this is exciting until the project reaches the 80% completion mark. There’s an invisible wall once most projects reach 80% completion. All the fun, creative, exciting efforts are completed. What's left are the tedious, little details that will make or break the project. If the Pareto Principle is any indication, the most important things are the 20%. This article will focus on the 20% an app must get right prior to its release.