It's an unfortunate fact of life that there's usually little to get worked up about Samsung phones. The Samsung D840 seems to be a rather unnecessary clone of the D900 – it manages to look like its predecessor in many respects. The phone is slightly slimmer than the D900, and has keys on the front panel that look quite similar. But to be fair, let's see if the phone has any hidden strengths.
The D840 is a slider phone, and its form factor notwithstanding, I still find Samsung phones to be the best sliders. The slide is the most comfortable of all things the phone can manage. Unlike the LG Shine, which I reviewed only last week, the D840 slides without effort.
The call/cancel keys, plus the five-way D-Pad and the select, back keys are all on the front panel, much as in the D900. I felt the keypad isn't as responsive as it should be when the keys are completely flat.
The memory slot is on the right side and the charging/earphone jack on the left with the volume keys. The camera is placed behind, on the exposed side of the phone, instead of sensibly keeping it protected under the slide. The 2.2-inch TFT screen can display up to 256K colors (240 x 320 pixels) and is good enough for viewing pictures.
Lovely phone except the battery. have been using it for nearly 7 months now, was one of the first purchasers. Bought 4 more within the family and am in love with it,. does not hang, does what you ask it to do, unlike Nokia and sony phones.. Sadly the charger cover is a bad bad design .D-840 does have a silencing' feature, just press the volume key down for a second when the phone is ringing. 
