Sadly, there are very few mobile browsers that aren't Chrome or Safari. In fact, Safari/Webkit is the only mobile browser engine available on IOS at all -- all

Sadly, there are very few mobile browsers that aren't Chrome or Safari. In fact, Safari/Webkit is the only mobile browser engine available on IOS at all -- all other browsers are just chrome (pun intended) around IOS webkit. To your point, https://caniuse.com/eventsource https://caniuse.com/eventsource Also there are polyfills for very old browsers like IE.