In the north of England (UK) they sometimes describe someone (or something) as a bit "twanky", "twankie", or even "old-lady" if they are not so quick or clever, especially when it comes to use of technology.
i.e. someone who isn't able to use a mobile-phone, or a DVD player might be called a twanky. If it's the device that's at fault, e.g. an old out-dated phone, then it would be the device/phone that would be twanky and not the person using it.
I don't know where this colloquialism originates - perhaps it's a reference to Widow Twanky.
The best way of describing it would be to say that you can use 'twanky' anywhere where you might say instead "my granny could do better".
I'm having a twanky moment.
S/he's a bit twanky.
It's very old, twanky technology.
Wow. I really did never know that the word "twanky" was ever used by anyone except us. The truth behind the word is that really, it is derived from "p'twankyho", a way of expressing one's feelings. Twanky has similar meaning, but is used to express slightly different emotion.