The iPhone 4: everything we know so far

Later this year, Tim Cook will stride onto the stage at Apple's Cupertino headquarters, and introduce the world to the latest iPhone.

And that's all we know for sure about the so-called iPhone 5. But that hasn't stopped the rumour mill from turning over some compelling clues. Between allegedly leaked parts, loose-lipped Chinese sources, inadvertent slip-ups in the latest iOS beta, and some active imaginations, we can piece together a pretty good idea of what the phone might look like.

A bigger screen

One doggedly persistent rumour is that Apple plans to use a larger screen on the next-generation iPhone.

Reuters' sources say that "the new iPhone screens will measure four inches from corner to corner", which would give it a roughly 30 percent increase in screen size, over the iPhone's current 3.5-inch screen.

Bloomberg corroborates the report, and references three people familiar with the matter.

References to the larger screen size can be seen in the beta for iOS 6. When9to5mac shifted the resolution of the iOS 5.1 simulator to the taller 640 x 1136, the iPhone operating system simply spaced the icons out to account for the larger real estate. On iOS 6, a fifth row of icons appeared.

If it came to fruition, a larger screen would put the iPhone on level ground with the majority of modern Android devices. On the downside, it would also give some developers a nasty headache when they realise they'll need to remake their apps to fill the new aspect ratio.

A smaller dock connector

The next iPhone may switch to a smaller dock connector, with just nine pins. It's a recurring feature in iPhone 5 parts and shells, that have supposedly been leaked from Apple's manufacturing partners.

More recently, a reference to "9Pin" has been found in the beta for upcoming operating system, iOS 6.

A smaller dock connector would give Apple more room to maneuver inside the iPhone's snug case. The firm could potentially fit more components in the shell, or sneak in a bigger battery. The only downside -- and it's a big one -- is that your current Apple accessories will not fi, unless the Cupertino company ships some kind of adapter.

A Nano SIM card

Parts of the new iPhone, allegedly leaked out of Usa, reveal that the iPhone 5 may take new "Nano SIM" cards. The iPhone 5's tinier SIM card tray has been present in a number of supposed part leaks, giving weight to the rumour.

These cards are 40 percent smaller than the current Micro SIMs used in the iPhone 4 and 4S, and were standardised by the European Telecommunications Standards Institute in June 2012.

"Today's SIM card designs take up a significant amount of space inside a mobile device," a spokersperson for ETSI said. "This space is more and more valuable in today's handsets which deliver an ever increasing number of features."