Early last year I wrote about using Remember the Milk (RTM) to manage my tasks. I even paid for a Pro account in order to sync to my iPod, but unfortunately, the lack of updates in both the main program and the iPhone app, plus having to deal with the often non-functioning reminder system eventually turned me to Google Tasks. Google Tasks is much simpler, but it integrates with Google Calendar and I could even have it send reminders to my cell phone.
A few days ago I noticed that Pocket Informant was on sale and they were donating proceeds towards the Haiti earthquake. I've been keeping an eye on PI for a long time, but the price always seemed just slightly out of my reach, but since it's on sale and giving towards a good cause, I immediately bought it.
Pocket Informant can only sync tasks to Toodledo (referral link) and not RTM. But in the ten months since I wrote my original post, Toodledo has improved by leaps and bounds and now completely meets and even exceeds my expectations. While I needed to pay for RTM's Pro version in order to sync to an external program, Toodledo's external sync is completely free. Toodledo's Pro version actually offers additional features such as subtasks (not possible with RTM) and longer retention times for completed tasks.
I also have PI sync my Google Calendar. Pretty soon I don't need to carry my laptop around any more. I still carry my Moleskine notebook around to take notes though. No matter how hard I try, I still find it much easier to take notes and doodle with a paper notebook.