For those of you opting out of buying one of the two new iPhones coming out this week, there's still Apple's shiny new mobile operating system, iOS 7, to consider. The software comes standard on the 5C and 5S, but Apple is also offering a free upgrade for previous generation iPhones starting today. But, just because it's new and everyone you follow on Twitter will be upgrading, does not mean the new OS is for you. Here's a little guide for the types or people that should and should not upgrade right now. 

If Your Home Button Is Sticky: Upgrade!

After years of use, the one and only button on the iPhone doesn't always work so well. Sometimes it takes two or three jabs to get it to do the right task: Like, get to the part that shows which apps are running, pictured at right. Buying a whole new phone would solve that problem, but for just zero dollars iOS 7 eliminates a lot of home-button pressing with its Control Center. It contains all the settings Apple believes you will use most, as Wired's Roberto Baldwin explains:

Screen brightness can be adjusted from here. You can toggle Airplane mode, turn Wi-Fi on and off, turn Bluetooth on and off, toggle Do Not Disturb, and turn Orientation lock on or off. At the bottom, there's instant access to the timer, the calculator, and the camera app. 

To get to the Control Center, just swipe up. That means more swiping and less tapping. 

If You're Using an iPad Mini: Don't Upgrade!

Several people have reported that the iOS crashes and has general bugginess on non-Retina devices, particularly the iPad Mini:

Those with an iPhone 4, a device some argue does not have a Retina display, should also proceed with caution. 

If You Want Everything to Work: Don't Upgrade!

As with any new iOS, there will be legitimate bugs. Already tech nuts have started complaining about some of the app design:

Others, like ArsTechnica's Andrew Cunningham, in his 15,000-word review of the software update, have complained about the animation:  

iOS 7 has more animations, which creates more opportunities for jank in the first place. It also has much larger animations, which makes the jank more noticeable when it happens. If you’re just scrolling up and down through a 2D menu, and your phone stutters momentarily, you probably don’t care and you may not even notice, but if it stutters in the middle of a big, broad, swooping Home screen animation, you’ll definitely be able to tell. It definitely looks bad.

The Verge also had the same problem with animations. 

If you'd rather avoid the growing pains: Wait. Apple will address anything terribly wrong in future iOS upgrades. "I’ll be surprised if a hypothetical iOS 7.1 doesn’t bring a few small but noticeable UI changes with it—this has already happened over the course of the iOS 7 developer betas, but with a wider user base comes the opportunity to respond to a wider (and more nuanced) range of feedback," writes Cunningham. Already the rumor bloggers say that Apple is working on improvements with both an iOS 7.0.1 version and a 7.1 version. Plus, you never know what the first mass upgrade will do to your phone. If you're at all stressed, at the very least, wait until tomorrow. 

If You Want the Latest and Greatest Apps: Upgrade! 

All the best and newest apps are going to design for iOS 7, not the old operating system. Even if you think the new "flat" design is ugly, as some designers do, the latest and greatest will be on iOS 7, as Cunningham notes. "No matter what you think of the design, if you’re an iOS user and you want to keep up with the newest features, you’ll have to come to terms with it, " he writes. "And even things that still bother me (the animations, first and foremost) can be tolerated because of the genuinely useful new features and additions that arrive with the update." Already a whole bunch of third-party apps have new looks for the operating system and they look modern and fresh. For example:

You can see a whole bunch of them over at The Next Web

If You're More than Okay with the Status Quo: Don't Upgrade!

The new iOS 7 is shiny and new, but the reviewers say that there's not much beyond the aesthetics. "iOS 7 is full of big, sweeping changes to that effect, and there’s real power in making something look fresh and bright, but in the end the new visuals don’t offer much change under the surface. Not yet, anyway," writes The Verge's David Pierce. As the iOS develops, he surmises it will improve. But it's not there yet. iOS 6 is full of tacky skeuomorphic design, but it'll do just fine for now. 

If You Want Customization: Get an Android.

Per usual, Apple has pretty tight control over what the software will do, as Cunningham explains:

You can't change your keyboard or set third-party applications as defaults. There are still pretty firm restrictions in place on what third-party apps can do in the background. Notification Center and Control Center behavior is configurable only within very narrow parameters.

That will hinder the overall development of the mobile OS, argues Pierce. "The Today screen could eventually be a fantastic Google Now-like experience, with all the information you need quickly, but only if developers can access it," he writes. Lucky for those who want more customization out of their phones, the Android OS has a lot more flexibility and phones like the Moto X and Nexus offer good options.