Word Trip
If you fancy a challenge and like Scrabble or word games, then your going to love this.
It's called Word Trip and its a free app available for Android devices (probably Apple iPhone / iPad too).
Me and Mrs Bread always play it and so far after about at least a year we have got about 40,000 points.
Highly addictive but great to play to keep your brain nice and sharp.
There are adverts on it, but while they are on you can always glance up at the TV or grab another beer / glass of wine.