Power & Source of Big Ideas

I used Sandisk and it works, but Android is too slow to the extent that i can't use it. Also is there a way to use SD cards larger than 4GB ?

thanks a lot for your help
Please I tried two SD cards (Kingston and Patriot) both are class 10 16GB and both are stuck at a rainbow screen and nothing happens. The blue led flickers, but nothing happens.

The same happens to me with the debain image

DietPi distro works for me.

Any help would be much appreciated
Thanks