Apple on Monday released iOS 4, the company’s new mobile operating system. There are a lot of people around the Internet that have posted their views on the OS, so I thought I’d roundup some of them for you. CNET: Hands-on with iOS 4 (photos)

Macworld: iOS 4: What you need to know

The latest update to Apple’s mobile operating system arrived on schedule, with iOS 4 becoming available as a download on Monday. As with past OS updates, iOS 4 delivers an array of new features and enhancements to some old favorites. But things are different this time as well—Apple is no longer charging iPod touch owners to upgrade. Then again, some customers with older devices won’t be able to upgrade at all—the first time that’s happened since the 2007 debut of Apple’s mobile OS.

Macworld: Hands on with iOS 4’s Mail features

In the time since the first iPhone was released, I’ve been one of Mobile Mail’s biggest fans and its biggest critics. I’m a fan because, for an e-mail client on a mobile phone, Mail is surprisingly usable. But I’m a critic because, as good as Mail is, it’s long had a number of glaring feature omissions that hamper its usefulness, and some of my biggest wishes for iOS 4 included filling those holes.

Ars Technica: Ars reviews iOS 4: what’s new, notable, and what needs work

iOS 4, previously known as iPhone OS 4, is a major update to Apple’s mobile OS which brings a handful of significant changes—namely Apple’s implementation of “multitasking” plus the opening up of thousands of APIs to third-party developers—while the rest of the improvements are basically tweaks to existing functionality.

TUAW: I’ve upgraded to iOS 4: Now what?

You’ve upgraded your iPhone to iOS 4, and you’re anxious to play with all sorts of new and wonderful features. Before you do that, take a few minutes to make sure everything is working as expected. Here’s a list of things to confirm. They aren’t in any particular order, and not all of them will apply to everyone, but some of them will, especially if you have “restored” your iPhone.

iLounge: Apple iOS 4.0

When we reviewed Apple’s iPhone OS 3.0 last year, we noted that “many users will remember it as a consistent base hitter, or ‘the version that should have shipped with the first iPhone’,” even though it included “extremely significant under-the-hood improvements” that mightn’t be fully appreciated at first. iOS 4.0 — the newly-renamed iPhone OS 4 — follows the same formula.