iDOS is an emulator for iOS devices that allows you to check out the early days of PC gaming.

There are six DOS games in iDOS, including the iconic Wolfenstein 3D. Games can be accessed from the library, and you can also use the DOS command screen, for PC purists.

Tap the top of the iDOS screen, and you can choose a floating PC keyboard, joypad, joystick or even mouse control. As with many iOS apps, these virtual controls are not great substitutes. iTunes file sharing has been disabled, meaning adding your own DOS programs isn't easy any more.

The games included have all aged a lot, and platformers like Duke Nukem never really stood up against the Marios of the world. Wolfenstein 3D isn't much fun today, and has been available on so many platforms over the past two decades, having it on iOS is nothing special.

iDOS is really only attractive to people who like the idea of playing around. It requires at least an iPhone 3GS to run smoothly, and even then you may find games suffer slowdown occasionally.

iDOS is hampered by the disabled iTunes file sharing and awkward controls. Emulating a old PC on iOS may be possible, but it's far from a match made in heaven.

Download iDOS 2.0.1 in Softonic

The operating system is very scaled back with only a few options like Microsoft Office suite and a few games. All documents created are saved in your OnLive profile, but any changes to Windows 7 is not saved and defaults every time it is opened.

Accessing OnLive Desktop through Wi-Fi, there was a noticeable lag in selecting icons to open programs or type text. It is a barebones experience and does not really serve a good purpose for you to consistently use it.

OnLive Desktop could have substantial updates to make the app more user friendly, but there is not a lot to offer. Even writing quick reminders in Microsoft Word takes more time than opening Notes on the iPad.

OnLive Desktop is only worth it if you spend a lot of time using OnLive.

Download OnLive Desktop 1.01 in Softonic

The TurboGrafx-16 GameBox, also known as the PC Engine was a much loved, but unusual console. Ahead of its time and expensive, it never competed well against Sega and Nintendo. However, many great games existed on the TurboGrafx-16, and this iOS emulator may be many people's first chance to play them.

Games cost $2.99, although the app is free and has one included game, World Sports Competition. The virtual d-pad controller is as good as we've seen, although it's never quite as good as the real thing. The selection of titles to buy in TurboGrafx-16 GameBox are a good range of 16-bit titles, from shmups to driving and platform games.

Other titles like the Commodore 64 app have better overall interfaces - TurboGrafx-16 GameBox could be better organized and a library of purchased games is lacking.

TurboGrafx-16 GameBox gives lots of forgotten console classics another chance to shine. The emulator works really well, and it's only really the interface that lets it down.

Download TurboGrafx-16 GameBox 1.4 in Softonic

Throughout the eighties, the Commodore 64 reigned supreme as the most popular home computer around. This iPhone app aims to reproduce the gaming side of the system, using the screen to give you a one button joystick to play games.

The Commodore 64 emulator comes with eight free games, including Dragon's Den, Jack Attack and International Soccer. There's also a shop with around 20 more titles, all at micro-purchase prices. Most of the titles are from the early to mid era, but include such iconic games as Uridium, Armalyte and Microprose Soccer.

The app is rendered in nostalgic Commodore 64 style, and the emulator itself works really nicely. Unfortunately you can only play games, and not access the original start screen - but this appears to be because Apple prohibited it.

The controls have been improved since the first versions, but still take a bit of getting used to, and they aren't ideal for delicate movements. But if you find a well-loved old game, you'll forgive these difficulties!

Commodore 64 will make people of a certain age hugely nostalgic, but younger gamers may (wrongly!) wonder what the fuss was all about!

Download Commodore 64 2.1 in Softonic