Joying / HuiFei rk3188 QuadCore 9813H, more RAM ?

i search for more APP Memory on the HuiFei 9813H as 1GB

1GB is verry low.....

can a update format the Memory so that it can be 3GB RAM and not so mutch NAND ? 16GB can 10GB
for save have i 2 SD Card Slots ... its mutch...

sorry bad english. i am german.

other devices it goes. MIC AV7

Joying RK3188 questions

Hi I have a Joying RK3188 and I'm wondering a few things before I install a custom ROM. First, if I do a custom ROM and MCU will I lose the phone mirroring? I've heard/read different opinions on this and it's a great feature that I do not really want to lose. Second, has anyone tried using it with a AT&T Mobley? Does it maintain the wifi connection? Third, does using a custom ROM allow me to set the power off time to something > 2 hours? I've read that the energy use is minor and that 24 to 48 hours should be fine without killing a battery. Finally, what's the difference between the stock MCU and the MCU with Sleep and Musik's mod?

Thanks.