However the A7 chip (also 64-bit) in the iPhone 5s is no slouch when it comes to gaming.
The App Store will contain games that run only on the iPhone 5s or even newer iOS hardware. If you love to play the newest, best-of-breed games, you may well miss out on those titles — or at least their full feature-set and performance abilities — unless you upgrade to Apple's top-of-the-line phone.
Our experience suggests that at least 32GB of storage is advisable for heavy gamers, although you can get by with less if you're willing to focus on a few games at a time, and uninstall them once you're finished.
iPhone buying guide: Which iPhone is best for business users?
Unless you're desperate to show off the latest iPhone while networking, or are big fans of gaming and movies in their spare time, business users can probably get by with an earlier model; a super-fast processor will be wasted if your principal needs are email, contacts management and light browsing.
However, the extra screen space is likely to prove useful if you are trying to produce documents and do other work on your iPhone and you don't already own an iPad. There are also some handy features on later iPhone models, such as the ability to make FaceTime calls over 3G and videoconference when outside Wi-Fi range: a handy option for the business-inclined.
iPhone buying guide: Which iPhone is best for sporty types?
If you already own a fitness monitor, or you are thinking of buying the Apple Watch (read: Apple Watch rumours, release date & images and our Apple Watch first look review), you may want to stick with an iPhone 5s or later, although Apple says that the iPhone 5c will support the Apple Watch.
Apple introduced the M7 "motion coprocessor" chip with the iPhone 5s in 2013 and this chip works in sequence with a fitness monitor to track the data without over using the battery in your iPhone. The new iPhone 6 and iPhone 6 Plus both offer an M8 chip. There is also a new Barometer included inside the phone — for blood pressure, not for telling what the weather will be like.
All Apple's iPad and iPhone models ship with iOS 8 and various apps provided by Apple for free. There are also thousands of apps available on the Apple App Store for you to download. Here are the 10 best apps for your new iPad or iPhone to get you started.
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