From the first - Kultakala - days there was a connection with mobile phones (Nokia once was on front and is Finnish, adoption of mobile phones in Finland was ahead of rest of the world). Ringtones and early - user-designed - logo’s were soon on Kultakala homepage. Throughout the years the option to download ringtones and wallpapers, next to games, was added in & again forgotten quite often. Early UK site even offerend some plastic covers for your phone (not really Habbo related, some partnership).
It got somewhat serious when in 2006 and beyond the ‘Habbo Shop’ was around. Part of Habbo homepage, selling games, shirts and related even (via Spreadshirts), and the ringtones/wallpapers. The wallpapers, at first, were a set of prede(f)(s)ined images.
Along with release of some games, though, some coders at Sulake made the wallpaper thing into an interactive application, Habbo Imager (picture source: Habbomatic). Meaning, option to choose back-/foreground, 1/2 detailed Habbo’s.
When the shop sorta silently did not return between updates Sulake abandoned Imager and all related ringtones/games.