3.Regarding X7MKII's internal storage and maximum storage expansion
The X7MKII's internal storage is 64GB;
X7MKII can support two micro SD cards with the capacity up to 256GB. Because there are 2 micro SD card slots, its maximum storage expansion is 512GB (256GB*2) at present. And the card of class 10 (or above level) is recommended.
Note: It is beyond our ability to test every brand micro SD card out there, and in general, it is suggested to use the major brand such as Sandisk.