It comes with 8 GB of built - in storage and also includes a microSD card slot for further expansion of memory. (androidadvices.com)
It has 16 GB of built - in storage and also includes a microSD card slot for further expansion of memory upto 128 GB. (phoneradar.com)
They both have 3 GB of RAM and both offer a 32 GB internal storage model, but differ in that only the One M9 offers expansion of that memory. (androidheadlines.com)