Everything analysts think will be in the next iPhone

The iPhone 6 and 6 Plus has seen record-breaking sales and profits, but Apple isn't resting on its laurels. The Cupertino company's 12-month refresh cycle means that the smartphone's next iteration is expected to drop this Autumn.

Apple remains as tight-lipped as ever about the device's specs and features, but this hasn't stopped people guessing. A new research note from Citi lays out what their analysts believe will be in the iPhone 6s (as they are calling it).

This includes:

• Two phones - again. Apple's tactic of selling the iPhone in two sizes has been wildly successful, and there's almost no chance the company will stop now.
• A better screen. Apple is already lagging behind Samsung when it comes to screen toughness, with the South Korean smartphone company using the latest Gorilla Glass 4 for its Galaxy S6. The iPhone 6, meanwhile, is still using Gorilla 3.
• Force Touch. One of the key features of the Apple Watch, Force Touch can detect how hard the user is pressing the screen, and react accordingly. Light presses can select an item while a harder one will bring up a menu, for example. The tech has since been integrated into the trackpad on the newest MacBook, and it only makes sense it will be used elsewhere too.
• Higher system specs. A no-brainer - every generation on the iPhone has come with higher specs than the one before it. Citi predicts a doubling of RAM to 2gb, and a better processor, probably the A9 chip built by Samsung. This may boost speeds by more than 25%.
• A redesigned camera. The rear camera, like other system specs, will see a bump - probably to around 12MP (the iPhone 6 is 8MP).
• Better casing. The iPhone 6s is expected to be an incremental upgrade, without a major redesign to its casing. But Apple may still improve the materials used, Citi argues, pointing to the Apple Watch's 7000 series aluminium, which is "60% stronger vs standard aluminium alloys." This could also avoid a rerun of "bendgate" - when some iPhone 6 owners' devices accidentally bent under pressure.

Citi expects that the iPhone 6s will provide another extremely strong year for Apple. The iPhone 6 saw unit growth of 40-50% year-on-year; the incremental upgrade of the iPhone 6s should see growth of 34% in the 2015 financial year.