Samsung’s anticipated next-generation Galaxy S smartphone has become surrounded by an iPhone-esque rumour mill, with the device expected to be announced in March ahead of availability in April.

With Samsung having sold 100 million Galaxy S series device since launch in June 2010, the line has become the only consistent competitor to Apple’s iPhone. It has seen roughly annual refreshes, and the current proposed timeframe is similar to that for previously incarnations.

According to reports, a version of the Galaxy S4 may use the eight-core processor unveiled by Samsung at CES 2013 earlier this year with 1.8 GHz clock speed, although there was also some suggestions it will use a 1.9 GHz quadcore processor, an upgrade to that in the current Galaxy S III.

With the current Galaxy SIII, Samsung uses a different processor in the LTE version (dual core) than the HSPA device (quad core), meaning that it is certainly possible it will offer variants of the new flagship powered by different chips.

The device is expected to include a 5-inch full (1080p) HD display, putting the screen size on the borders of the ‘phablet’ category – and having crept up incrementally from 4-inches on the first Galaxy S. Other mooted features include a 13 megapixel camera.

In addition to the hardware changes, the device is expected to see some software innovations. This could include some “touchless” input support, for example with raising the device to an ear automatically answering calls.

Also mooted was eye-tracking technology, based on patents filed by Samsung using the name “eye pause” and “eye scroll”. The existing Galaxy SIII uses eye monitoring to know if a user is reading a screen, in order to intelligently dim screens when not in use.

It was also suggested that following the pattern seen with the Galaxy SIII, a “mini” version of the Galaxy S4 may be in the works, with an official launch slated for May.

Likely to have a 4.3-inch screen and 720p HD display, other specifications mooted include an 8 megapixel camera, LTE support and integrated NFC.

It is worth noting that in some ways, the Galaxy SIII Mini is closer to the Galaxy SII than the full-fat Galaxy SIII, meaning the Galaxy S4 Mini may prove closer to the existing Galaxy SIII.