Whether you are trying keep young passengers entertained on an interminable car journey or idling away the hours of a long haul flight, the ability to watch a TV show or feature film of your choice while on the move is invaluable.

Until recently, the only means of doing so was a portable DVD player with a built-in screen. This remains the most straightforward option and as these machines have tumbled in price recently it represents a relatively modest outlay. They are compact, lightweight and come with a built-in power supply so you can take them out of the car and finish watching the film when you get to your destination.

The more tech-savvy may prefer a gadget able to play compressed digital video files. These files will usually either have been downloaded from the internet or ripped from a DVD, in much the same way as CDs are commonly converted to MP3.

The best software for that specific job is HandBrake (free at tinyurl.com/dmlrv).

Once downloaded or ripped from a DVD to your computer you need to transfer the files to your portable gadget. The upside of this is greater flexibility and not needing to carry a collection of DVDs around. The best known example is the iPod Video, but there are plenty of other choices. As all of these devices, including the DVD players, can play music and show digital photos as well as video, they have been given the generic, albeit none-too-snappy, moniker of portable media players (PMP). The PMPs that do not play DVDs are collectively known as MP4 players.

Like so much in life, portable video involves compromise. The bigger the screen, the more enjoyable the movie. Yet a larger screen also means a chunkier and less portable device that will often have a shorter battery life too. Each style of player has its own issues: DVD-only models won’t fit in your pocket but do tend to have larger, more detailed screens. They are simpler to operate too. Conversely, MP4 players are usually more trim and versatile, yet they can prove fussy in terms of which video formats they will accept.

Once an MP4 player becomes too pocketable, you will be squinting your way through The Lord of the Rings, which is fairly pointless. Most also require some faff with a computer to transfer video onto them, so you must decide if the convenience is worth the effort. An exception is the eminently flexible Archos MP4 player, which handles most video formats and also records programmes directly from a TV if you buy an optional docking cradle.

The good news is that you can play files from a computer on some portable DVD players and thus benefit from the bigger screen. This is because many portable DVD players will handle at least the most common form of compressed video (DivX) if the files are burnt onto a blank DVD. This means you can squeeze an entire series of Desperate Housewives – or Bob the Builder – onto one DVD. You will lose some quality in doing so over a standard DVD, but this is far less noticeable on a portable screen than a full-sized TV. The Philips DVD model reviewed here will also play compressed MPEG-4 movies directly from a USB memory pen too. All of the players on test can also be connected to a TV, allowing you to watch on a bigger screen – useful in a hotel or holiday villa.

Technophobes may rightly balk at handling compressed video files or converting them to the correct format. Though you do pay extra for the fancier features outlined above, there are other compelling reasons for investing in a decent-calibre portable DVD player. Cheaper models often have inferior screens that look insipid and may not respond well to the rough and tumble of life on the road.

All of the larger players here can be attached to the rear of a car seat’s headrest – a vital tool for keeping young passengers occupied en route. In testing, InGear paid close attention to viewing angles to see how practical it was for several people to watch at once.

JARGON BUSTER

Flash memory A solid-state memory chip commonly used in cameras that’s less fragile than a hard drive

MP4 player A gadget that supports the MPEG-4 standard for video files

MPEG-4 A popular compression format (or codec) used for video files. DivX is a type of MPEG-4 standard.

PMP (portable media player) Generic name for portable players that can display images and music from a variety of sources

Reviews by David Phelan All prices include Vat and delivery

TICKET TO RIDE

Sony DVP-FX850 – typically £250, or £225 from www.amazon.co.uk

Great screen; ideal for the car

This classy DVD player, out next month, has a clamshell design yet the screen pivots and locks to create a compact shape while viewing. As the controls are on the lower part of the screen, they remain accessible. This, along with twin headphone sockets and excellent 5hr 10min battery life, makes the Sony ideal for in-car action. The glossy 8in screen is top class, producing bright, rich colours. There’s a socket for a USB memory drive but the Sony only plays photos or MP3 files from this. To enjoy compressed-video movies (DivX format only) you must first burn them to a blank DVD. Overhead lighting caused some reflection. Nevertheless, the screen’s flexibility minimised this and it was the only model with even a modestly watchable picture in strong sunlight. Pricey, but worth it.

MR MUSCLE

Archos 704 wi-fi – typically £337, or £282 from www.dabs.com

Versatile video all-rounder that can record TV

This tablet-style MPEG-4 player is the ultimate gizmo. The 40GB hard drive is equivalent to eight blank DVDs but can house every episode of 24 if the video is compressed. It handles a vast array of formats, records directly from a TV (with the optional £54 dock), and can even connect to the web with wi-fi. The 7in screen is touch-sensitive, which proved an effective way to access the player’s controls, although firm prodding was required. The removable battery lasted 5hr. Picture quality relied on the video source but a decent MPEG-4 episode of Battlestar Galactica from a PC looked impressive, if not as sharp as a DVD. The Archos is as chunky as a paperback book, and at 22oz isn’t overly light. For gadget power, though, it’s top dog.

MAGIC TABLET

Philips PET830 – typically £180, or £163 from www.amazon.co.uk

A generous screen and neat tricks

This decent-value DVD player is unusually of tablet design rather than being a fold-up model. It comes with a car-headrest mounting kit to keep younger passengers busy on long journeys and Philips claims this will fit all makes of car except Volvo. Many portable DVDs have poor viewing angles, but like the Sony this one will entertain a brace of brats with its sharp, watchable 8.5in screen, and the speakers are decent. The Philips played compressed-video files from a DVD or a USB stick (either DivX or clips shot on, say, a mobile phone) and had a modest battery life of 3hr. But its exposed screen is more damage-prone (for example, if thrown into an overnight bag) than is the case with a clamshell model.

POCKET ROCKET

Creative Zen Vision W – typically £270, or £211 from www.pixmania.com

iPod-beater with a good screen

This widescreen version of Creative’s Vision MP3 player is optimised for video. It’s noticeably larger in size than an iPod Video, but the 4.3in screen (compared with the Apple player’s 2.5in) is far better for watching films, while the 4hr of movie-playback battery life also tops the iPod. Transferring files from a PC was easy with Windows Media Player, and the Vision W played most video formats. It remembers your spot in a movie if you break off to listen to music, and the 30GB hard drive houses reasonable amounts of film and music. There’s an FM radio, a microphone for voice recording, and a Compact Flash memory card slot makes for easy photo viewing. It was the best player on test for pocketability, but will you really enjoy a movie on such a weeny screen? It’s no looker either.

A TOUCH DISAPPOINTING

LG MFFM37 Touch Me video player (4GB) – typically £160, or £150 from www.beyondtelevision.co.uk

Highly portable but poor features and insipid screen

This pocket-sized MPEG-4 player has a classy brushed-metal casing and a neat 2.4in touchscreen. It weighs just 2.3oz, yet contains 4GB of flash memory that is less damage-prone than the hard drives of the Archos and Creative models. The supplied computer-based software was effective, albeit basic, and transferred any type of video file to the player, regardless of whether or not it could play it. The player’s menus were plodding and we needed dainty fingers to make headway. Ultimately, though, the LG was badly let down by its small, low-resolution screen, which simply wasn’t sharp enough to make viewing fun. No dice.

LOW-RENT REGRET

Toshiba SD-P1707 DVD portable – typically £130, or £98 from www.dabs.com

Lightweight but flimflam budget option

This tiny Tosh DVD player is keenly priced and weighs in at a trim 1lb 9oz. The carry case folds out to become a support stand for in-car use. The angle of view on the 7in screen was acceptable and there are decent basic features, including the ability to play DivX compressed-video files from DVDs. However, there’s no comparison between this model and the Philips or Sony. The screen was a disappointment, colours looked garish and even proper DVDs lacked detail or subtlety. The silvery casing felt cheap and it’s poorly balanced too.

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