I'm here to see how many people make their own apps for this :-) It feels like the cliche of both programming and time management to want to build a tailor-made system for tracking tasks, instead of just doing tasks.
I use a bunch
- RememberTheMilk (RTM) as the real todo app.
- Send myself emails for urgent stuff.
- Google calendar only for appointments, I stopped using Google tasks because I wanted a single place and RTM was better.
- Pocket for "reading" todos, i.e. articles I plan to read.
- Google docs for organizing ideas.
- Things written on paper if it's likely to be done within 1-2 weeks.
- Joe's Goals for habit tracking sometimes (super simple).
- In code, I leave todo's with my name (I have an autocomplete for that).