Don't look further than Gmail as your task management tool on your smartphone or desktop browser. Gmail app on iPhone is not like the regular mail app that only keeps your emails for X number of weeks. All the emails are there and the searching is so easy. Labels/Folders are easy to use and it is easy move things around or apply different labels.
Don't get me wrong. I like my OneNote for all the work related items, but for simple tracking of my to-do personal items, I have been using Gmail app on my iPhone and Gmail in the web browser.
I created two labels:
Before the beginning of the week, I review my backlog and put it under Current if I plan to work on it that week.
Then throughout the week, I review the Current list and I work on the items.
For regular bills I made reoccurring meeting in Google Calendar and I set up reminders to get emails when I have to pay bills. Those would go under my Current list for the week.
With this system, I feel so organized.
Yes, there are very good tools that I tried that do this much better on the mobile device, but I could not find one that does it great on both desktop and mobile. For example, I love OmniFocus app for iPhone, but I don't have anything for my PC at home or at work. I paid premium to to play around their iPhone app, but I decided that Gmail is the best all-around solution for me.
I will do another post about Gmail and how it also works as a useful note-taking tool.