Basically, I’ve had some little problems with the app on my Samsung Note 4.
The lessons won’t show up on the app. Example, if I’m loading one of Evgueny’s lessons on his course, “Советы учителя” it won’t load all of the lessons. It caps out at lesson 23 and anything past that won’t show up. This is true for a lot of courses.
Also, a similar parallel problem is that when lessons have been deleted from the library, they show up on the app. Example, the русский подкаст course only has so many lessons. It seems the original creator deleted at least half the lessons and they still show up on my phone.
I’m trying to be as specific as I can describing this, so I hope this paints a picture.