Like the 780 and all the other models in the mju range that don't have "SW" in their name, the 830 is weatherproof. That means you can use it in the rain without a problem, but it is not actually immersion waterproof. The exact specification is "IEC standard publication 529 IPX4", which means it should be able to withstand water splashed from any direction, but does not specifically include resistance to dust or dirt. It also says nothing about shock resistance, nonetheless the mju 830 is very well made, and despite its low weight it feels very solid and robust.
The control layout, also identical to the 780, is excellent, with large easy-to-use buttons with illuminated lettering, making them much easier to see in the dark. The controls are very simple and straightforward, as befits a very simple point-and-shoot camera. The main mode dial has only six settings, including the standard program auto mode, a scene mode with 22 options, a "favourites" album playback mode, the very useful Guide mode found on many Olympus compacts, and a movie mode. Or at least, that's what they call it. We'll come back to that later. The main menu is also very simple, although as usual it has a superfluous start page. Camera menu options are limited to white balance, ISO, drive mode, two metering options (ESP or spot), three AF options (face detect, spot or iESP) and a panorama stitching mode. As well as this there is also a small function menu for commonly-used shooting options, including another appearance by ISO, white balance and drive mode, as well as the option to choose full auto, which disables even more of the camera's options in favour of total auto-everything simplicity.
Although the 830 has a very limited range of features, those that it does have are useful. The 5x zoom range gives it a bit more versatility than your average compact, although it would have been even better if the wide-angle end of the zoom range was a bit shorter than 36mm. The 180mm telephoto end is useful though, especially when combined with the dual anti-shake system. This consists of both a moving sensor image stabiliser and an ISO booster to provide a faster shutter speed. Fortunately it is possible to override this part of it by manually setting the ISO, in which case it is possible to take sharp hand-held shots at around 1/15th of a second, which is pretty good. Some other features are also very good, such as the LCD monitor which is very sharp with an excellent refresh rate, and has an exceptionally wide angle of view. Others are not so good, such as the movie mode, which like that on several other Olympus compacts is rather poor. It can shoot at 640 x 480 resolution and 30 frames per second, but only for 10-second clips. If you want longer clips you have resort to 320 x 240 (QVGA) resolution, which gives you 29 minutes of shooting time, but only at 15fps. With a number of rival cameras now offering 720p HD movies at 30fps the 830's video mode looks pretty weak by comparison.