I recoloured an artwork that is on Google Arts and Culture. I have used a limited colour scheme of golds and silvers. I did this on an iPad and enjoyed the process.
https://g.co/arts/k3YXB12EEKBv2Zrp6
This is the original artwork by Peter Shire. it is created in the Memphis style with whimsical colours, forms and uses industrial materials.
https://artsandculture.google.com/asset/menorah-2/nwGgV2DXq77xDQ