Can I swap memory from one phone to another one?

Sep 7, 2018
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My Galaxy S4 mini won't turn on anymore, it didn't fall or anything, it just died. I tried to change the battery, I tried all the tips I could find online and nothing work.

Can I buy another second hand galaxy s4 mini and swap the internal memory so I don't loose all the info I have inside? I don't want to loose all my contacts's phone.

Is that possible?
 
Or how can I be sure that my phone is synced to my gmail account so I can safely buy another phone and recover my contacts with my gmail account?
 
Well I went to a repair shop and my mother board is dead, is there any possibility to weld the part that holds the info into a new motherboard?