Facebook surpassed analysts' expectations as its revenue soared in the last quarter of 2015, driven by mobile ads and user growth. It topped $5bn (£3.5bn, €4.5bn) in quarterly revenue for the first time in its history.

The social networking said its fourth-quarter income more than doubled to $1.56bn (£1.09bn, €1.43bn). It now has a total of 1.59 billion users, of whom 1.44 billion are active on mobile devices.

Following the results, Facebook's shares rose 7.5% to $94.45 (£66.27, €86.8) on the Nasdaq on Wednesday (27 January), valuing the company at over $275bn (£192bn, €251bn). Its shares were trading even higher in after-hours trading, rising to $105.32 (£73.89, €96.79).

Facebook's robust growth in an uncertain economic climate in the US is seen as remarkable. Meanwhile other tech companies like Apple and eBay are facing challenges, with iPhone sales set for a decline. Instagram, the firm's photo-sharing app, has begun selling ads after crossing 400 million active users, while the social media firm's aggressive investment in the mobile messaging service WhatsApp is also paying off.

An analyst at MKM Partners, Rob Sanderson, commented on Facebook's unprecedented growth, opining that since their "core business is so strong" the company will probably not face much opposition in relation to its investments in virtual reality (VR) or even face demands for it to monetise its other properties.

"It's phenomenal at these (currency headwind) levels that they're accelerating to that level of growth," he told Reuters.

Facebook has been sharpening its focus on futuristic tech options like VR, artificial intelligence and drones in a bid to connect every part of the globe to the internet.