Use ”index colour” to colour reduce in Photoshop on iPad pro?

Hi!

I use Photoshop for illustration. In order to print on textile I always need to colour reduce my illustration and specify colour. To do this I use "index colour" 

Now Wien i starten working on iPad Pro I souldrottningen like to do the same thing. Is this tool available in Photoshop on iPad Pro?

Next question is. To change colour i use the tool "selet colour" in Photoshop on my computer. If i hage à solid black detailing bur sant the to be Brown for exempel I use select colour to select all blacks and swap to Brown. Is there and any way to do this in photoshop on my iPad pro?

thanks!

/ Joanna