Android/iOS/Blackberry: There are lots of apps that can send "free" text messages, but most require your recipient to also have the same app. JaxtrSMS is a free service from Sabeer Bhatia, founder of Hotmail, that can send free texts to any mobile number in the world, and display it to the recipient as coming from your own phone number.

Fancy 20 per cent off at a nearby restaurant? Optus' new Go Places app includes discount vouchers for "thousands" of restaurants — but the vouchers themselves aren't free.

iOS/Android/Symbian: Fring, one of our favourite mobile apps for VoIP calls, just released a new iPad app that supports four-way video calling between the iPad and non-iOS users. They also updated their iPhone, Android and Symbian versions to match.

The players in the smartphone OS market that we talk about most often at Lifehacker - iOS and Android — essentially work on a "one platform to rule them all" strategy, and seem to do pretty well out of it. But does that mean that every manufacturer should follow that template?

We'd be lying if we said Symbian phones got a whole lot of attention here at Lifehacker, but they do still represent a large chunk of the market. The new Nokia N8, which is being pushed as a serious photography device as well as an apps platform, will go on sale across all the main carriers on November 1 for an outright buy price of $749.

iPhone owners are frequently convinced they see other iDevices everywhere they look. Android owners believe they're poised to take over the universe. But current sales and future projections on smart phone ownership from Gartner show that the mobile world is more complex and more diverse than we give it credit for.

Rocking a Novia phone and got an itch for some VoIP calling? Starting today, you can grab the Skype for Symbian app from the Ovi Store for free.

Smart phones are becoming an increasingly common choice even for casual users, but the whole area can seem confusing and overwhelming for new buyers. Lifehacker 101 guides you through the main platforms available.

Windows Mobile/Symbian: Opera has released version 10 beta of their popular mobile browser. If you put a lot of miles on your mobile browser, Opera Mobile 10 has quite a few new features and tweaks worth the update.

Android/Symbian: FlyScreen saves you the trouble of unlocking, clicking and waiting for an app to open to get calendar items, weather updates, SMS messages or just about anything else by putting swipe-accessible widgets on your "lock" screen.

Modern phones come loaded with bright screens, fun games and apps, and connections for 3G, Wi-Fi, Bluetooth and GPS. Not coincidentally, they're constantly out of juice. Here's some of the best collected wisdom about saving your web-connected phone's battery life.

Windows Mobile/Symbian/BlackBerry/Android: If you've got an itch to flee your smartphone for another platform entirely, the prospect of manually dragging over your data is daunting. Sprite Migrate, a free transfer application, makes it easy to transfer pretty much everything.

Mozilla engineer Christian Sejersen announced today that Firefox Mobile (codename Fennec) will be released for Symbian phones by the end of April, 2009—complete with full browsing features. The bad news: Sejersen says we shouldn't plan on seeing Firefox Mobile on the iPhone, BlackBerrys, or Android any time soon due to "technical or licensing reasons." If you're curious about what Firefox Mobile will offer once it's released, check out our screenshot tour of Fennec.