The subscription will appeal to people who use Office apps on traditional Windows or Mac computers or Windows tablets, such as the Surface Pro 3. It's a smart move by Microsoft, but it makes me wonder whether you really need a subscription, which starts at $70 a year. The company now offers Word, Excel and others at no cost on most mobile devices. Just as I was warming up to choosing a Microsoft Office 365 subscription over making a one-time software purchase, Microsoft started giving away a lot of subscription benefits for free.