The app just has a really clunky interface IMO. Some sort of menu system to speed changing between the different areas of the app would make it more usable.
The desktop version also lets me see all the info I want on the recipe creation screen. Water volumes for mash and sparge, and some other parameters that I like to keep an eye on can be added to the right-hand column.
To be fair, I'm not much of a smart phone user. Once I have my recipes built I write everything in my log, I find I do a better job keeping a physical log updated vs. a digital one.