I had a really nice chat with the founder of Citymapper and one of the topics of discussion was around how to properly put in place a long term brand strategy, to create first a short term distinctive mark, and in the long term to build up their growth strategy.
So I created this icon as an example to show how to make a mark distinctive and unique while keeping the current product feeling in place. The logo at the center is a play with origami, arrows, diamonds and planes (3 planes). I called it "diamond arrow" even if, it's not definitely an arrow. ;)
Citymapper is the most complete app out there for travelling in London, check it out: http://citymapper.com/