By Rachel Armstrong SINGAPORE (Reuters) – Tiny Singapore does not look at first sight like one of Apple Incs priority markets: it has no official Apple Store and doesnt even rate a mention in the companys latest annual report. Apple South Asia Pte Ltd, however, its Singapore entity, booked $14.9 billion in revenue for the 12 months to September 2012 – more than it would have received had the countrys entire 5.3 million population each bought an iPhone 5S, an iPad Air and a MacBook Pro. There is nothing illegal about the accounting practices employed by the computer giant, which, like many multinational companies ranging from Google Inc and Microsoft Corp to BHP Billiton and Huawei Technology Co, uses the city-state as a key hub for its Asia business. Singapore has so far largely stayed out of the debate raging in Europe and the United States about the ways multinationals try to lower their tax bills.