10 things in tech you need to know today

Good morning! It's another sunny day in London. Here's all the tech news you need to know this Friday.

1. Apple Watch preorders start today! The smartwatches don't go on sale until later this month, but Apple started accepting preorders this morning and will let potential customers try them on in-store (with appointments).

2. Reviews are in for the new MacBook - and it's a mixed bag. The new Apple watch is ultra-thin and looks amazing, but this portability comes at the expense of power. Reviewers almost unanimously say it's the future.

3. Facebook is considering a new mega ad exchange that could prove a serious threat to Google. The social networking giant's potential plans were revealed in new patent filings.

4. Xiaomi, a red-hot Chinese tech startup, has sold more than 2 million smartphones in just 12 hours. The flash sale was part of a "festival" to celebrate the company's fifth birthday.

5. Apple spent $38 million over the last month promoting the Apple Watch in TV ads. That compares to the $42 million spent on TV ads touting the iPhone 6 and 6 Plus over the past 5 months.

6. LinkedIn bought online learning company Lynda for $1.5 billion. It will help broaden the remit of the professional services-focused social network.

7. Amazon got the go-ahead from US regulators for new drone tests. American regulations are infamously strict on drones, forcing many US companies to test the technology abroad.

8. Google might be building support for the iPhone into its Android Wear smartwatch software. It will make Google's smartwatches more competitive with the Apple Watch, meaning Apple users aren't forced to go with the Cupertino company's offerings.

9. Amazon took another step in its plan to make business PCs obsolete. It is launching a desktop app store that allows you to subscribe to business software on a monthly basis.

10. Amazon is suing sites that provide fake product reviews. It's the first time the online retailer has done so.