Since form tends to follow function in the camera world the overall design is much like most other ultra-compacts, something which hasn't changed much since the original Pentax Optio S in 2003. It has the usual D-pad with flash, self-timer, EV compensation and macro mode, as well as four buttons for playback, shooting mode, menu and delete. The zoom control is a rotary bezel around the shutter button. Despite its small size the control layout leaves room to grip the camera, with a small raised thumbgrip on the back.
The S225 is a very simple point-and-shoot camera, and as such it isn't exactly overburdened with exciting new features. Shooting modes consist of a basic Auto mode, a scene mode with 17 scene programs and a sound recording option, a face-detecting Smile Shutter option, and a movie mode, which is limited to 640 x 480 resolution and 30fps, with mono audio. Video recordings are limited to 25 minutes in length.
The main menu is also very limited, but there are a few options. Image size, ISO setting, white balance and drive mode (which include and interval timer) can all be adjusted of course, and there is a short list of colour options as well, including vivid colour, pastel shades and cyanotype. There are a few AF mode choices, including manually selectable AF point, centre focus and face priority. There is also a distortion control option, which is just as well because the lens produces a lot of barrel distortion at wide angle.
The S225 has no mechanical image stabilisation, but that doesn't stop Nikon from claiming it has 4X Anti Blur, which is precisely why marketing people should always be kept away from things they know nothing about. It has electronic image stabilisation, but it's not terribly effective.
There are also some options in playback mode, including a quick fix function that adjusts exposure, and a D-Lighting function that recovers some shadow detail in high-contrast shots, although as usual it does introduce some image noise and slightly slow down the shooting speed.