I think it will have a positive impact on bitcoin and other cryptocurrencies, because iOS is one of the well-known brands in the field of technology development, therefore the presence of the bitcoin symbol in iOS products means it is a pretty good bitcoin marketing strategy because it works with known brand, this will increase investor confidence and interest in bitcoin and automatically this will increase the price of bitcoin.
It will really turn to a positive impact simply because some IOS user will notice the symbol of bitcoin and afterwards they tend to search it and they will try to buy bitcoin. So if they tend to buy bitcoin the demand on market will increase so the result is high price on market.