Today's Tech: Apple gets to work as security issue hits iOS 7 and Microsoft announces Windows 8.1 prices ahead of big release

Growing smartphone and tablet sales mean a major boost for app downloads in 2013, which are forecast to top 102 billion by the year's end. That dwarf's 2012's 64 billion downloads, thanks in large part to the Apple and Google stores, according to data from Gartner. The research firm's numbers suggest that free applications account for more than 90 per cent of 2013 downloads. In-app purchases, which will drive 17 per cent of store revenue this year, will increase to 48 per cent in 2017, but eventually slow down in later years.

Two NHS websites have been hacked and defaced by Haxor Hussy (H4x0r HuSsY), a member of the Pakistan based Madleets group. The affected websites were both small subdomains for hospital library services in the south west of England. One site is designed to enable book lending between south west, Wessex and Thames Valley hospitals. The other is for users to get information about health education books available in libraries across the south west region. "Struck by H4x0r HuSsY. Security breached by Madleets," the hacker wrote on the websites. Both have now been restored. The websites are built using WordPress and it appears that the hacker exploited a vulnerability in the system in order to breach them, The Hackers Post reports.

Though Microsoft will offer Windows 8.1 as a free upgrade for existing Windows 8 users next month, the Redmond-based company this week provided details on how much it will cost to upgrade to 8.1 from an older version of Windows. In the US, consumers will be able to download Windows 8.1 via Windows.com or purchase it in store as a packaged DVD. The standard Windows 8.1 will cost $119.99 (£75), while Windows 8.1 Pro will set you back $199.99 (£125), which is similar to the current pricing structure for Windows 8. Windows 8.1 is scheduled to start hitting the shelves on 17 October. If you can't wait another month for some reason, you could purchase Windows 8 now and then upgrade to 8.1 for free when it is released.

Apple has assured iOS 7 users that it will fix a problem with the lock screen that leaves various apps vulnerable to manipulation by anyone with access to the device. The lock screen problem allows anyone that has direct contact with the device to easily gain unfettered access to various social media accounts by sharing photos from the photo album. The hack works on the iPhone 4S, 5, 5C, and 5S, as well as the newest version of the iPad. Soon after the problem was discovered, Apple told Forbes that it is "aware of this issue" before stating that they'll "deliver a fix in a future software update" before adding that it "takes security very seriously."