Even though I run a small business and consult on the highly linear topics of strategy and tactics, I am a creative. Although creativity enhances my abilities to contribute in problem solving and the aforementioned strategy and tactics, it can also manifest itself in me noticing every proverbial “squirrel” that runs by.
So, one of the tools I use is Wunderlist. I use the free version primarily to keep electronic task lists on multiple devices. I am currently an Apple user, so it does very well syncing between my iPhone, MacAir and iPad. I believe it is a cross-platform App, but I can’t speak to the non-Apple use. I also like that it is not web-based, so I can use it offline, in airplane mode, etc.
Hope this helps!