CalDV and ICS Calendar Subscriptions
Hmm. It's nice that the iPhone will now support subscriptions to Google, Yahoo, and iCal calendars. Here's one better. The Cydia-based application NemusSync lets you perform two-way synchronizations between your iPhone and your Google Calendar. To get all of your calendars onto your iPhone, subscribe to them using a single Google Calendar account and let the free application pull down any updates right onto your iPhone.
New Stocks Application
Apple is packing a new version of its Stocks application into the 3.0 firmware update, adding additional information and related news to the stocks you've selected. Only, these features have been a part of any number of official App Store applications for some time now. Most of these apps require a one-time fee to use. But if you're just looking for a Stocks application that combines chart-watching with related news, check out Bloomberg.
Bluetooth Blowup
The new 3.0 firmware will include support for Bluetooth-based peer-to-peer networking as well as the long-awaited stereo Bluetooth functionality. These are difficult tasks to replace with software, so we had to find an in-the-ballpark Bluetooth application that promotes similar functionality. Fire up Cydia and check out iBluetooth, which allows you to make file transfers across devices using, well... Bluetooth. You can also grab SweetTooth, a stumbler that scans for nearby Bluetooth-broadcasting devices.
Note synchronization
Frustrating is the situation of updating to new iPhone firmware, only to realize that you forgot to save all the notes you made in the device's Notes application. The 3.0 firmware will now synchronize these notes with your desktop, but you can also do so using the free App Store application (and online service) Evernote or the US$25-per-year application/service Remember The Milk. The Cydia-based app iPhoneNotes is a great notes synchronization tool for Mac users that doesn't require a separate online service to act as a central hub.
Shake It
Polaroid pictures, get ready: You can now enable the Shuffle mode in the iPod section of your device by merely shaking it as if it were an unruly can of pop. Other applications that blend physical gestures with common iPhone uses include the Cydia-based mCoolPhone, which lets you shake your phone to answer a call or flip it upside-down to hang up. For music enthusiasts, there's Pocket Touch, which lets you control your iPhone's jam session by swiping or tapping your finger in various ways.