Are we about to plunge further into the cyborg era?

Nokia, once the largest cell phone supplier in the world, has filed a patent application for a tattoo that will alert users when their phones are ringing.

The tattoo is able to detect a magnetic field and transmit a ‘perceivable stimulus’ — from an incoming call, text, status updates, or low-battery signal — to the user. There will be an option for several different vibration signals — similar to different ringtones — to differentiate callers.

I can envision some applications (e.g.: emergency workers) where this could be a useful invention; but, for the average person, the idea seems a little too weird.

Note: the user won’t be forced to acquire a tattoo, there are several other options: stamping a ferromagnetic pattern on the skin; spraying the ferromagnetic pattern onto the skin; attaching adhesive tape (containing the ferromagnetic pattern) onto the skin; and drawing the ferromagnetic pattern onto the skin.

The ‘perceivable stimulus’ can be any stimulus; including, but not limited to, vibration and/or impulse movement of the skin. I assume itching, tickling, and heat sensations are possible.