Samsung is preparing to make big announcements for both the Android and Windows Phone platforms with new Galaxy and ATIV device unveilings.

The South Korean tech giant has a big event scheduled for June 20 in London and on Monday, May 27, Samsung decided to do some teasing for the upcoming "Premiere 2013" show.

The poster for the event mentions only "GALAXY & ATIV," which indicates the event will primarily focus on Android and Windows Phone-based devices. The teasers further feature partial shots of three mysterious devices: one may be a tablet or a phone (or perhaps a "phablet?"), another one looks like a convertible laptop and a third device seems to be a camera, potentially the rumored Samsung Galaxy S4 Zoom.

According to the press release, the big unveiling will take place at Earls Court 2, London on June 20 and it will be livestreaming on Samsung's YouTube channel from 6 pm/ BST/ 1 pm ET/ 10 am PT. The teasers aim to give readers an intriguing glimpse at what to expect.

The new Galaxy Android device may be the much-rumored Samsung Galaxy S4 Mini, but the company may also announce multiple devices at the same time. The Galaxy S4 Mini is simply the most likely scenario, especially since the pint-sized device made a brief appearance on Samsung's official apps website. The company later pulled the entry, but rumors of an imminent launch already spread like wildfire.

When it comes to the ATIV range, meanwhile, we're talking Windows Phone. The ATIV lineup is Samsung's relatively new plunge into the Windows Phone mobile operating system. The company launched its Samsung ATIV S last year, but the handset failed to make much of a splash. Nokia still commands the small market share Windows Phone managed to grab in recent years, but Samsung seems poised to make its own mark. Recent data from research firm IDC shows that Windows Phone just passed BlackBerry in terms of market share, so it makes sense that Samsung aims to bolster its position in this space as well.

It remains unclear at this point just what Samsung plans to unveil at its June 20 event, but combining Android and Windows Phone unveilings is an interesting move nonetheless. It's also worth noting that Samsung's event will come just one week after Apple's annual Worldwide Developer Conference (WWDC), where the Cupertino giant typically makes significant announcements regarding upcoming software and hardware. Microsoft's 2013 Build conference, meanwhile, is scheduled to kick off on June 26 and the Redmond company will likely unveil the Windows 8 update dubbed Windows Blue.