i tried that app and apart from being counter-intuitive to use (it requires a lot of useless processes) once it's done is not only ugly to see (i have removed it since 8.1 DP) but it's also not practical. Android shows a CLICKABLE exploded...it means once you click on it the icons of each app become live and clickable. What app folder does is creating a dull container for some apps, making a tile and trying to show what's inside.
It's a terrible implementation of how it should work. Go try, just to say one, Nova Launcher on any Android and try the level of flexibility you have. You'll see what i mean. Don't even mention Themer and the alikes.....they just bury WP in terms of UI customization.
Another issue i have mentioned many times is the way WP aggregates mails. It's very confusing and not practical for people with multiple accounts.
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