Let's start with the hardware. Jolla jumps into the fray wielding a 4.5-inch touchscreen display. Some of the other details are decidedly non-specific, such as what brand or speed dual-core processor is inside and how much RAM is baked in. It has 16GB of internal storage, a microSD card slot, an 8-megapixel rear-facing camera with auto-focus, and 4G LTE support.
As for the physical design, the battery is user-replaceable, and there's also a feature Jolla touts as the "Other Half," which is in reference to the handset's removable backplate. One neat thing about the backplate is that the software will change its interface to match your selected color and design.
Jolla runs on Sailfish, a Linux-based mobile OS. It's essentially a retooled version of MeeGo with elements of the Mer Core project, though it has the advantage of being able to running Android applications. It's heavily focused on gestures.
Pricing for Jolla is set at €399 (around $513 USD) with pre-orders sales underway. It's expected to ship by the end of the year.