1) It's hard to detect when to fallback. You'd have to set up a list of user-agents you've tested and code around their individual issues. This is not ideal. 2

1) It's hard to detect when to fallback. You'd have to set up a list of user-agents you've tested and code around their individual issues. This is not ideal. 2) It doesn't solve the iOS problem (which, as this post points out, has even more issues than desktop browsers)