RIM, the manufacturer of the BlackBerry push e-mail mobile device, has posted a 57% jump in second-quarter profits as it fights off increasing competition in the market.
Net profits at RIM for the quarter to 31 August were $111m (£65m). The company's total sales for the period were $490m, which was up 58% on the same quarter last year.
RIM said it had added an extra 620,000 BlackBerry subscribers in the quarter, bringing the total of users to 3.65 million worldwide.
Businesses that have equipped their staff with BlackBerry devices also buy e-mail server software from RIM to enable employees to access their messages and other applications.
A number of smaller rivals offering push e-mail solutions to businesses have sprung up in the last 18 months. Microsoft is also developing its Exchange server collaboration platform to take business away from RIM.