Color contrast for aged and color blind? [ Edited ]

[JedTheRealFish]

When card price changes, sometimes it’s difficult to see red or green on anything. Perhaps art crew could adjust altered card prices for more contrast?

[Kermo3]

And on smaller display it's really difficult to spot all numbers, they are so small..

[jaydabbler]

I have (what used to be at least) great vision - but I have a REALLY hard time reading that green number on yellow background on my iphone 6s