Apple chief executive Tim Cook extended his buying spree with the company acquiring speech-recognition software company Novauris Technologies to help improve its Siri service.

Apple did not disclose how much it paid for the British firm. The team behind Novauris have worked for companies including Dragon Systems, which makes dictation software.

Siri: Apple's assistant may improve with the company's acquisition of Novauris. Credit:Bloomberg

The deal fits with Apple's approach of acquiring smaller companies and then swallowing the teams and technology before releasing related features in future products. The strategy contrasts with peers such as Google and Facebook, which have been spending billions of dollars on acquisitions.