Microsoft's Office refusal risks opening door to rivals Microsoft's refusal to release its Office software for rival tablet computers risks eroding its most profitable product and has inspired a new generation of start-ups that are racing to fill the gap, according to tech executives and analysts. Microsoft has restricted users of the iPad and tablets running Google's Android software to an online version of Office that only works when the machines are connected to the internet. The strategy of holding back the full software for Windows tablets has failed to ignite sales, however, forcing the company to take a $900m writedown on its Surface tablet in July. Box, a US cloud storage company, has become the latest to join the rush to create new productivity tools for office workers, announcing a beta, or test version, of a word processing service earlier this week called Box Notes. Aaron Levie, chief executive, said that the weakening of Microsoft's PC monopoly lay behind a spate of similar new Office competitors. "Innovation was sucked out of the industry for 15 years," he said. We're trying to go after a new category of information people aren't storing at the moment. Box joins a growing list which includes start-ups such as Dropbox, Evernote and Quip, which have followed Google in developing online services intended to replace aspects of Office, particularly on new mobile devices where Microsoft no longer calls the shots. "For a long time, even if you had a product in this area, you couldn't make a business out of it," said Bret Taylor, co-founder of Quip and a former chief technology officer of Facebook. Microsoft for the first time doesn't own the platform. Julia White, a Microsoft marketing executive, said the new rival services were "very niche" and did not approach the "full solution" of Office. She also said that users relied on being able to access their work on PCs, tablets and smartphones, making it important to use a single productivity tool across all devices. Microsoft's Office strategy is likely to come under scrutiny later this week when the company holds a hotly anticipated analyst meeting, with Wall Street becoming increasingly frustrated by its foot-dragging on tablets. "They should be aggressively pushing that business rather than leaving the way open to competition," said Rick Sherlund, software analyst at Nomura. Putting Office on Apple and Google's tablets "would be my first suggestion for new management," he added. The decision to give up the extra business Office could have generated on rival tablets in order to increase the attractiveness of Windows machines is a "strategy tax," said Mr Taylor. What's good for Office might not be good for the rest of Microsoft. In one sign of the company's efforts to appease Wall Street, Microsoft on Tuesday raised the quarterly dividend on its shares by 5 cents, or 22 per cent, and renewed a $40bn stock buyback plan due to expire this month. The dividend increase, which lifted the yield on its stock to 3.4 per cent, followed increases of 15-25 per cent in the previous three years. Microsoft's grip on productivity software is unlikely to be weakened in the short term, though failing to occupy tablets risks leaving the door open to rivals, according to analysts. "I think right now it's pretty locked up," said Wes Miller, an analyst at Directions on Microsoft. The Microsoft Business Division, whose sales come almost exclusively from Office, generated nearly as much profit as Windows and the server and tools division combined in the past 12 months. However, workers who travel with only a tablet and smartphone may learn to live completely without Microsoft software, Mr Miller said. They created a window of opportunity for people to have to find out what it's like to live without Office. The start-ups challenging Office also hope to use new forms of digital collaboration among workers to gain an edge. The word processor from Box, for instance, lacks many of the features of Microsoft's Word, but is designed to make it easier for groups of workers to share information and to work on the same documents simultaneously. Most of the new collaboration tools are stripped-down services that are deliberately far more "lightweight" than Office, said Alastair Mitchell, chief executive of Huddle, another collaboration start-up. "All the storage and sharing of information will be in the cloud," he added.