Piste maps are fine, but they rarely give enough information for the more adventurous skier or snowboarder. Increasingly freeride areas are shown on piste maps, but the more adventurous freeride areas don’t figure. Which is a shame, because there are many relatively safe freeride areas away from the main pistes that can be undertaken without a guide. The Gemsstock and the Laub (off Titlis) are two of the best examples you can explore without donning skins or snowshoes. Whilst the pistes go one way in Zinal, Verbier, Glacier 3000, Lenzerheide and many other resorts, you just need a little local information to flip off the other side of the mountain and experience untracked snow.
So where do you go for more information if you don’t speak the language well?
Although the best guides for ski or snowboard touring and freeriding Switzerland are in German, there are two map series that show all the information you need to plan a route with English annotations. One is produced by Freeride Maps at 1:25,000 and the other is the Federal Office of Topography Ski Tour map Series 1:50,000 series (for which a separate, free English-language list of the conventions used is available). Both are good, but expensive at about SFr 25 or so for each map.
I had hoped that the Atlas of Switzerland would provide this information but it doesn’t, and the user interface is not intuitive, the documentation is poor, it only works down to 1:100,00 and includes relatively little useful information for the winter sports enthusiast (although you can figure out slope inclines). Nice idea, not so well executed. And I can’t reproduce the rather neat 3D images you CAN produce with it because the copyright restrictions are pretty Neanderthal.
If you use a GPS there are some great tools for you. Garmin have about 100 resorts in Switzerland mapped, although off-piste is not addressed. Don’t knock Google Maps, either. It has some useful information including the locations of most significant lifts. BTW Switzerland insists on using it’s own mapping system, the Swiss coordinate system (or Swiss grid) is different from the usual latitude/longitude system used elsewhere.
Finally, a disclaimer. Go off-piste only with a guide if you are not an experienced freerider. The mountains are indifferent.