I've always been interested in Windows Phone 7, but decided on Android (HTC Inspire) instead. After having that phone for about six months (right after the Android 2.3 update was released), it started having all kinds of problems, so I decided to look into an upgrade. My boss at work had a Samsung Focus and loved it, plus the Windows Phone Mango update had just come out at that time, so it seemed like the right time to try out a Windows Phone. I went with an HTC HD7S because I have never liked Samsung's phones (I had a Samsung Jack... worst phone I ever had), with the express intent of upgrading to the HTC Titan when it came out because it was due to come out within a month of my upgrade. I loved that phone, but wanted 4G speed, so it was either the Titan or the Focus S that would be my next phone.
Well, the Titan ended up coming out the week AFTER my return period ended on the HD7S, so I didn't have much choice. In retrospect... it might have been the luckiest mistiming ever.
The first thing you notice on the Samsung Focus is the design of the phone. It's wafer-thin, much like the rest of the Samsung Galaxy II line. Pick up the phone, it feels as light as you would expect, but doesn't feel cheap. The only qualm I have about build quality is the battery door is a bit flimsy.
Turn on the phone and you'll be greeted with one of the most beautiful phone screens you've ever seen. The Super AMOLED screen on the Focus S is crystal clear, rivaling the iPhone 4S in color and clarity. With the screen on, the black background of the home screen is so deep it's nearly impossible to tell where the screen ends.
The phone's camera is an 8 megapixel shooter with flash, autofocus, and digital zoom. The camera takes great photos. The only gripe here is the camera has a very wide field of view, so everything is very small unless you zoom in, and zooming in with the digital zoom causes the clarity to suffer.
Battery life on the Focus S is very good. I routinely get a full day's use out of the phone with constant use. Once I even forgot to plug the phone in overnight and it still had at least 15% battery life remaining when I woke up. (There's no numerical display for battery life, but at 15% the phone will start to warn you that battery life is low.)
Most importantly, the Windows Phone 7.5 (Mango) OS is one of the best phone OS's I've used. I've used iOS, Android, and BlackBerry, and Windows Phone 7.5 tops them all in almost every area. Frequent Facebook user? Windows Phone 7.5 integrates Facebook into the OS. No need for an app; everything is handled natively. The same goes for Twitter as well. Because of this OS level integration, Windows Phone 7.5 can do some things that other OS's struggle to handle, or can't do at all. For example, every contact has a "What's New" and a "History" page, which show you everything that contact has posted on Facebook and Twitter accounts of theirs that you're following, as well as a history of everything they have done directly with you, be it Facebook shares, phone calls, texts, emails, etc. You can pin your most frequently used contacts to your home screen, and the Live Tile for that contact will show you the most recent action from that contact's What's New/History page.
Quite possibly the best part of Windows Phone 7.5 is its email handling. The Outlook client for Windows Phone 7.5 is outstanding. Message threading is an absolute GODSEND for people like myself who work in a position where they are routinely dealing with multiple people about the same project. Messages are grouped by subject, so you can trace an email thread in chronological order from start to finish in one place, regardless of which folder that email actually resides in. No more missed replies because you didn't check all your email folders for new emails, no more confusion when emails come in out of order, everything is all in one place. This alone has saved me countless hours of tracking down emails multiple times. I'll never be able to go back to unthreaded emails. The email client syncs up to Hotmail, Microsoft Exchange, POP3/IMAP, and Gmail, and handles them all with ease.
One of my biggest issues with Android (specifically Sense UI from HTC, but I noticed this on other Android handsets as well) is AutoCorrect. The AutoCorrect functionality in iOS and Android annoys me because it forces you to change a word if it detects something it thinks you meant to type. Not so with Windows Phone 7.5. It will correct most simple mis-spellings automatically, but when it comes across a word it can't determine, it handles it much better than iOS or Android does. Instead of forcing you to change the word to what it thinks you meant, Windows Phone 7.5 will simply leave it underlined with the red squiggly line you know and love from Microsoft Word. Clicking that word again will bring up the suggestions, or the option to add it to the dictionary. A simple change, but BRILLIANTLY executed. Also, the Windows Phone 7.5 keyboard is just about as perfect as you can get. It's an absolute dream to text on. Typing out a full-length email is about as painless as it can possibly be on a handheld device. I send most of my emails from my phone, and it takes me no longer to do it from the phone than it does from my desktop.
The bottom line? The Samsung Focus S, with WIndows Phone 7.5, is an absolute powerhouse of a phone and should be high on anyone's list, especially if they are using the phone for business. You will not be disappointed.