Research firm IDC today released its preliminary calculations of PC shipments for the first quarter of 2013, finding the worst year-over-year performance in the nearly 20-year history of its tracking studies.

Following today's introduction of Facebook Home , a new people-focused integration layer for Android devices, Fortune has published an interview with Facebook CEO Mark Zuckerberg in which he discusses a number of topics including the rivalry between Apple and Google in the mobile market. In Zuckerberg's view, the open nature of Google that has allowed Facebook to build Home offers a great opportunity for advances in the user experience that are considerably more difficult to achieve within iOS given Apple's control over the platform

Apple today rolled out a new advertising theme for the iPad on its website, highlighting a number of reasons why people love their iPads. The campaign follows on a similar one for the iPhone that launched a couple of weeks ago. The 'Why iPad' pages mention positive J.D

Digitimes is reporting that Apple is set to cut shipments of iPad mini in the second quarter of 2013, according to its industry sources. The cut is said to be a 20% reduction for the month of April, with steeper cuts potentially following in the remainder of the quarter, although the report does not specify whether the cuts are relative to previous production plans or to current-quarter output. Apple has reportedly cut its shipments of the iPad mini to between 10-12 million units for the second quarter of 2013, according to industry sources.

The iPhone 5 that will be sold through T-Mobile is a modified version of the A1428 iPhone 5 that is currently produced for AT&T's network, among others. The new version of the A1428 has been tweaked on the hardware side by Apple to support Advanced Wireless Services (AWS) bands for T-Mobile's network . According to an Apple representative that spoke to Engadget , existing A1428 phones cannot be updated to add AWS support.

CNET reports that T-Mobile will finally announce plans to sell the iPhone at tomorrow's " Uncarrier " event in New York City. T-Mobile, which is the only one of the four major carriers that does not currently offer the iPhone, originally confirmed that it would begin selling Apple products at some point in 2013. Image via @evleaks In addition to an iPhone announcement, the event is expected to feature an announcement about T-Mobile's plan to end device subsidies and introduce contract free phones as part of an overall rebranding of the company

RBC Capital Markets analyst Amit Daryanani has released a new research report today citing supply chain checks as the basis for predicting a June or July launch for both the iPhone 5S and a lower-cost iPhone, in line with other recent reports. Daryanani says, however, that the lower-cost iPhone appears set to omit a Retina display. Our supply-chain checks indicate that AAPL is working to launch multiple new phones in the June/July time-frame this year

Apple today rolled out a new advertising theme for the iPhone on its website , highlighting a number of reasons why people love their iPhones. The campaign comes with all-new graphics, a new "Why iPhone" page , and an email promotion.

Tmonews reports that T-Mobile is prepping an anti-AT&T ad campaign in retaliation against the full page anti-T-Mobile ads that AT&T released last week . AT&T's ads, which were posted in The New York Times , The Wall Street Journal , and USA Today , criticized T-Mobile for dropped calls and slow download speeds. T-Mobile's retaliatory ads question why AT&T attempted to buy the carrier if T-Mobile's network is so unsatisfactory.

Piggybacking on Bloomberg 's latest report about Apple's "iWatch" plans, The Verge has weighed in with its own claims about the project.