Looking to keep on top of the latest headlines in small business, innovation and tech? Check out our Weekly News recaps posted every Friday morning-- a quick summary designed to keep you current.

Instagram has hit 400 million monthly users. Facebook founder Mark Zuckerberg and Instagram co-founder Mark Systrom celebrated the milestone this week by taking a stroll on to reflect on the photo-sharing app's future.

Uber unveils a new kind of carpooling service in China. The ride-sharing company will debut this approach in China before launching it in other markets.

And Apple's "iCar" could arrive sooner than exepcted, putting it in direct competition with companies like Tesla.

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