There are two ways to change them. One is a relatively simple method built into iOS 18 and the other is a bit more advanced ...

While there may be debate about whether iOS 19 will be a UI revolution or evolution, there does seem to be a consensus view ...

Interestingly, these design changes were first spotted way back in early 2023 during WhatsApp's development phase. Beta testers got a glimpse of the updated icons in iOS apps before Android users did.