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The SGH-S400i is one of Samsung's new i-mode handsets, available on the O2 network, the only one offering the i-mode service at the moment. Of all the Korean giant's i-mode phones, it has the lowest specifications, but due to its slide form-factor, small size and unmistakable Samsung styling, it's attracting plenty of admirers.
The S400i is available free on a £19 monthly contract or for £170 on pay as you go.Design
The S400i is a small, light slider phone
The rest of the handset is a dull metallic grey colour and has a smooth and curved design. The S400i only weighs 88g and is small, measuring 91mm by 45mm by 21mm, and it feels comfortable to hold. The slide mechanism is smooth, but if you open it with one hand, as most people do, it's quite easy to mistakenly press the soft keys and activate an application as you open it.
When the slide is opened you're presented with a small but functional keypad. All the keys, including the ones on the front, are black with backlit white numbers and symbols. Each key on the keypad is slightly raised at the bottom and this makes them very tactile. However, the keypad feels out of balance when the handset is fully opened. The top half of the handset feels heavier than the bottom and tends to lean forward unless you hold the handset with your entire hand. Another niggle is the bottom of the keypad, where the keys are narrower than at the top and this makes pressing them slightly awkward.
If you're right-handed, you may find the silver volume button on the left side of the phone badly positioned. Unlike the Nokia 6111, which had a volume button that sat just under your thumb, this button involves you using your forefinger, which can be awkward, depending on how you hold your phone.
As with most Samsung phones, there's a cover over the charging port on the bottom and a headphone port on the right side. The covers are relatively easy to open and give the phone's surface a more flush appearance. The battery doubles up as the back casing of the phone and has a quick release button to pop it out when you need to replace it or change the SIM card.
The on-board camera is a 0.3-megapixel (VGA) photo and video camera and comes with a flash and a portrait mirror. As with the D500, the camera is cleverly hidden behind the front section of the phone and protected by the back section when closed.
i-mail lets you receive email from your O2 i-mode email account as if it were a text message. This means you can forward mail from your existing accounts to your phone and read them on the go. You can also send emails via your O2 i-mode address straight from your mobile, in the same way you would a text message.
i-mode gives you access to a plethora of sites including shopping, news, sports, music and banking sites. Some of the sites are free and others require a monthly subscription, which costs around £2. A few sites offer useful services such as the ability to plan a journey, play the lottery or find a job.
All this is done on a 176x220-pixel screen, which is small for viewing Web sites. However, it is bright and sharp. The two top soft keys underneath the screen can't be reprogrammed, so you're stuck with i-mail and i-mode buttons, whether you want them or not. The navigation key in the middle can be programmed to open four different applications, though. This includes accessing the camera, which although it has many shooting modes and effects, unfortunately only has a VGA resolution. The camera can also be switched to video mode and can shoot around a minute of film.
Even if you do decide to take pictures or video, there's only 13MB of internal memory to store them on and no memory-card expansion slot. Presumably that's why Samsung didn't bother adding an MP3 player to the handset. You can however store and listen to four short AAC or MP4 files.
Overall, the S400i has most of the features you would expect on a mobile phone: it's triband, it has a voice recorder, an alarm, Java games, a speakerphone, Bluetooth and a decent interface. It has some annoying traits too, though. It doesn't have infrared, which isn't as powerful as Bluetooth, but is more reliable. It can play polyphonic and AAC ringtones, but not all of them can ring and vibrate at the same time.Performance
The audio on calls is very clear and loud. The speakerphone works well but is complicated to access while driving, because you have to go into the menu and select speakerphone 'on', instead of just pressing a button once. You can always use a Bluetooth headset but Samsung Bluetooth connectivity can be testing at times and Samsung sources have revealed that compatibility is an issue.
The VGA camera takes blurry and pixellated photos that turn blue when the flash is used. The video suffers from the same problems and overall you will probably not use this to take anything else but MMS and contact photos.
The battery life is acceptable and lasts for around three to four days on standby and two to three hours' talk time. This will provide you with enough battery life to last you a couple of days of heavy usage.
Edited by Mary Lojkine
Additional editing by Nick Hide