I have got new ui update 2.5. Now my question is should I backup my data? If I upgrade ui without backing up my data,  will the data(including files and apps) be lost? Please, whoever upgraded your M21, let me know....

Hello guys, I have been using samsung M21 for 1 month. Today a new ui update just arrived. I upgraded my ui 2.0 to 2.1 and what happened you won't want. The camera performance just dropped. Colour of pictures are washed out. Even, there is a auto foc...