The latest patent for the Apple iPen suggests that the product will be a modular pen with a number of add-ons, including a projector.

The pen, which currently has 22 patents on record, is thought to be in development by Apple and is expected to be a stylus-style pen for use with an iPhone or iPad.

However, the most recent patent released by the technology firm suggests that the product could have a number of additional modules to expand its use, including a camera module, a laser module and a projector module.

According to the patent, the projector module would allow the pen to project images onto a wall so documents could be edited mid-air. With the further addition of a camera, the pen can also detect the wall to ensure pen position accuracy.

The camera module can also be used independently and is capable of wirelessly transmitting photos to other devices. The module with integrated audio recorder will work in a similar way, whilst providing users with additional record, stop, play, fast forward and rewind buttons.

The latest iPen patent suggests that the device will be charged wirelessly via a base module, but it also hints at the possibility of a USB connection via the pen's tip.