Island whiskies are produced on any of the islands around the perimeter of the Scottish mainland. Islay is not included and is seen as region on its own. Island whiskies tend to be somewhat in the middle of Islay and Highlands whiskies. They are slightly less smoky than most Islay whiskies, but smokier than most of the other Scottish regions.
Some of the most well-known Islanders are Highland Park (produced on the island of Orkney), Talisker (Skye), Jura (Jura), Tobermory (Mull) and Arran (Arran).
A whisky I have written about before in a twitter tasting, but I think it deserves its own blog post. The Douglas Laing’s Rock Oyster blended malt Scotch whisky is a firm favourite. Rock Oyster was released in 2015 as a blend of single malts from Scottish islands, including Orkney, Arran, Jura and Islay.