Maybe others have the same problem as me.
I changed from Palm OS based phone to Nokia E70, which is a very good mobile, first-class communicator, but terrible PDA. (Much more cheaper with mobile contract than my Treo was, and has built-in wifi)
Calendar could be used, but Todo and Notes applications do not support categories, and Nokia PC Sync does not sync categories.
Now there are 2 third-party applications that try to extend the built-in PIM applications, the Papyrus and the AquaCalendar.
I am trying both application paralell before I buy one. Both have good developer support and they are waiting for improvement requests and recommendations.
Much bigger problem is that Nokia PC suite does not sync categories, so I can do GTD only on my mobile, I lost the possibility of using Outlook efficent. Maybe Nokia will solve this problem.
I hope other GTD-ers using Symbian based phones try to send good ideas for developers, maybe we could get a very good PIM which fits to GTD as much as possible.
Any other GTD related experiences relating to Symbian/Nokia?