The look and feel inside is equally practical and nifty. Since it is an app, the in-built instructions on how to navigate it are welcome:
Here the same icon appears next to “contents overview”, but transformed, because it is a different view.
Yet another view, the topic index search. Again, the icon tells you which environment you are in.
Do you remember that grammar point you searched a while ago? The app remembers it for you.
And if you want to keep tabs of the grammar points you like, you can create favourites. Remember your old book full of bookmarks and highlighted sections?
Although I wonder what this is doing in a grammar book, I think it is very welcome anyway in a reference book.
All in all, it is as complete as the book on which it is based, the interface is simple and practical and it allows to manage the information in useful ways. The creators seem to have had in mind what people use the book for, and so the result is really functional. Because I am a sentimental, sometimes I go back to my old paper version, but I can carry this around with me, even in my phone!