Facebook and WhatsApp have received a letter from the US Federal Trade Commission reminding them about user privacy.

In February, Facebook announced that it was planning to acquire messaging service WhatsApp in a deal worth $16 billion (£9.6 billion).

This week's podcast starts with news from Microsoft about an update to its Windows Phone platform and a cost-free OS offer to hardware manufacturers.

There's also a new flagship smartphone from Nokia, a roaming announcement from the European Parliament, a UK virtual mobile network from The Co-operative Group, a change at the top for Mozilla, retail expansion for Vodafone and an awkward end to BlackBerry's relationship with T-Mobile in the USA.

The licence that permits T-Mobile to sell BlackBerry products in the United States won’t be renewed this month, according to the Canadian smartphone company.

Instead it will expire on 25th April 2014.

Microsoft has revealed details of its forthcoming Windows Phone 8.1 mobile operating system, which will be installed on new phones from this month and will also be available as an update to current Windows Phone 8 users in the near future.

This new version of the Windows Phone OS will offer a virtual assistant called Cortana, named after a character in the Halo video game series.

A new research report by Berg Insight predicts that revenue from mobile location-based services in Europe will grow from €735 million last year to €2.3 billion (£1.9 billion) in 2018, which is a compound annual growth rate of 25.8%.

Meanwhile, the North American mobile location-based service market is expected to grow at 16.1% per year from $1.8 billion in 2013 to reach $3.8 billion (£2.3 billion) in 2018.