Call Quality, Messaging, Browser
The Samsung Focus S supports AT&T's "4G" HSPA+ network. During my tests it was capable of hitting download speeds of nearly 4Mbps, comparable with other AT&T HSPA+ phones in the same areas. Upload speeds were a bit slower than expected though, topping out at only 0.67Mbps. The Focus S supports the new Internet Sharing feature found in Windows Phone 7.5, but use of it requires a tethering plan from AT&T.
Calls on the Focus S were loud and clear, though the audio lacked the depth found on other smartphones. Callers were able to hear me without issues, and the speakerphone got suitably loud without distortion, but had the same thin-sounding qualities as the earpiece.
As with all Windows Phone 7.5 smartphones, the Focus S features an integrated messaging client that supports SMS/MMS, Facebook Chat, and Windows Live Messenger. Conversations are threaded and grouped by contact, regardless of which service the conversation is being held in. The system makes it easy to bounce from Facebook chats to SMS conversations and back without breaking step. The app also supports group messaging, but I wish that Microsoft would support Google Talk and AIM in addition to Windows Live Messenger and Facebook Chat.
Windows Phone 7.5 includes a powerful email client that supports POP3, IMAP, and Exchange accounts. Most web-based email services will configure automatically, and the app supports linking of multiple inboxes into a single view, threaded conversations, multiple message management, and full HTML email. The Windows Phone 7.5 email app is one of the best available on any mobile platform, and makes processing large amounts of email simple and easy.
AT&T managed to keep pre-installed carrier apps to a minimum on the Samsung Focus S. The user is also given the ability to remove the apps as desired. The Focus S also has Samsung's Now app and Microsoft's excellent mobile Office suite installed out of the box.
Unfortunately, while the Windows Phone Marketplace has seen significant growth in the past year, and now is home to over 40,000 apps, it does not offer nearly the quantity of apps in the Android Market or iOS App Store and a number of big name apps are still not available for the platform.
The Samsung Focus S features Microsoft's Internet Explorer 9 Mobile browser, which provides a fast browsing experience and support for multiple windows. Web pages load very quickly, and pinch-to-zoom and scrolling are effortless. It does not support Adobe Flash, which might be a deal-breaker for some, and since it lacks support for WebKit rendering, many mobile-specific sites do not render properly with it.