CREATE TABLE table_6247 ("Windows" TEXT, "Mac OS X" TEXT, "Linux" TEXT, "Other Unix" TEXT, "AmigaOS" TEXT, "Android" TEXT, "Windows Mobile" TEXT)

Which AmigaOS has a Windows Mobile of no, and an Android of no?
SELECT "AmigaOS" FROM table_6247 WHERE "Windows Mobile" = 'no' AND "Android" = 'no'
SELECT "AmigaOS" FROM "table_6247" WHERE "Android" = 'no' AND "Windows Mobile" = 'no'