Post Sniffing Rules
Although browser sniffing used to be quite popular, it’s now gone out of fashion (for good reasons) and has been deprecated (if not dropped) by popular libraries such as jquery.
The better way is to do feature detection.
Exception To The New Rule
However, there are times when you might be targeting (for whatever reason) a specific browser. iOS safari is a good example, as are other mobile browsers, as the mobile platform has different ui concerns.
My Particular Purpose
For my purposes, I want to target IE specifically in order to alert the user to use another browser.
You may not agree with what I want to do, but please disregard that in your answer.
With this in mind, what the best, most reliable way to detect browser versions, more specifically any IE version, and iOS Safari too.
Is it safe to still use jquery.browser?
Use Conditional Comments. The are a perfect fit for what you’re after.