Same address failures trump isolated errors.
And it's a good news, since it allows to blacklist a few error-prone cells to improve RAM reliability much more easily than by swapping the entire hardware components.
However since mobile devices do not use ECC memory, memory errors, leading to crash or corruption stay undetected and non fixable.
Discussion on Hacker News: https://news.ycombinator.com/item?id=10616428
DRAM’s Damning Defects—and How They Cripple Computers
An investigation into dynamic random-access memory chip failure reveals surprising hardware vulnerabilities