Sony Ericsson's P-series touch-screen Smartphones have been very successful with the business segment and it's been a while since the once reigning P910i came out.

The M600i is not a new upgrade to the P-series (the P990i has just entered the market), but rather an alternative for those business users who prefer not to have a camera in their phones, because of security and privacy restrictions at work, or any other reason. Internally, the two phones are almost identical. The M600i also runs Symbian OS 9.1 UIQ 3.0, does GPRS, HSCSD, 3G/WCDMA but no EDGE. The phone has around 64mb of internal memory and a Memory Stick Micro M2 slot for expansion. The few things that make the M600i differ from the P990i are the absence of WiFi, a camera and FM radio tuner, putting the P990i into a kind of "business multimedia" category and leaving the M600i to do just business.

The M600i is more compact than the P990i (10.7cm high, 5.7cm wide, 1.5cm thick) and lighter (112gm). The touchscreen is also of the same resolution (240x320), although it's wee bit smaller in size. The most notable difference (other than the black color of the M600 vs. the silver on the P990i) is the absence of a flip down keyboard / numpad. The new integrated keypad is a 5x4 grid with an inset 3x4 grid for the numeric keypad. However, each key taps on either the left or the right, effectively doubling the width of the grid into a 10x4 one. The 10x4 grid offers you a full QWERTY keypad, including a slightly wider space bar (which also doubles up as the 0 number key), backspace, enter, shift, alt and left/right cursor keys. Having used the P910i's ineffective QWERTY keypad, I feel this one is definitely much easier to work with. Initially the dual-sided keys may take a bit of getting used to, but if you're fast with the regular PC keyboard, you'll pick this up fast just like I did. All the keys have a shift position, but only the side rows have commonly used symbols. Even so, certain commonly used symbols like the underscore need to be inserted via the menu. Typing numbers in a text area (like an SMS or an email) is also a little uncomfortable because you have to click the Alt button before each digit. An alternative is to hold the Alt button pressed, which is still not as comfortable as the usual numeric mode that all regular phones offer.

Overall, the phone works good for SMS and email, which is why its the M-series, or Mail series. Speaking of Mail, the M600i comes with Exchange Active Sync which is available as a free download from the Sony Ericsson WAP site.

Of course, handwriting is still available with the M600i just like the P-series. I usually can never manage to type a single word without making mistakes using handwriting, but I did seem to have a better success rate with the M600i. Either the UI is a little more tuned to accept a wider range of written characters, or my handwriting has actually improved since I last wrote on a piece of paper, which is something I'm not very sure about.