Hi, I know it is not a priority, but have you considered using SBTCG images of cards (if permission is given ofc). They have a decent quality English scans on their website and I have noticed there is a mix up of images being used in the simulator, ranging from JP to EN, JKTCG, official WS with watermark. I understand it is a lot of work, but my OCD would be grateful if there will be more consistency.
I am also most grateful for Android version!
Great work!