To begin with Samsung make great phones and tablets they are usually 
quicker to bring out new features out ahead of its competition, such as face recognition, Oled screens etc, while Apple usually waits a while until those new advances become more proven. So as a consequence of this their products often feel that they are in beta compared to iOS products.
Another thing that is to the detriment of Samsung is its reliance on the Android OS. Samsung should have fully adopted Tizan as its main os for its phones and tablets. At the moment Tizan is doing well in the Samsungs tv line up and the Samsung watch line up. If they could fully adopt Tizan they could trim the OS to work to its best with Samsung hardware so you get the maximum performance interns of battery life and in hardware performance. With Android running on 1000’s of different devices and with devices often running on older versions it often makes it difficult for app developers to deliver a polished app experience like on iOS. 
The only reason they have not moved fully over to Tizan for its phones and tablets is due to sheer lack of apps available to the Tizan OS. That is the achilles heel of the OS like it was to the Windows Phone OS, which lead to the downfall of the Windows phone OS. What they could do like Microsoft Windows could have done is to have enabled Android apps to function on the OS, then these os’s could have flourished.
