GPE programs aim to meet the relevant freedesktop.org standards.
GPE programs should comply with the GNOME Human Interface Guidelines where it is appropriate. Some deviations have to be made to deal with peculiarities of the palmtop environment, such as small screens; some of these changes and additions to the GNOME HIG can be found on the GPE HIG Wiki page.
OpenOffice has a project for Document Editing on Small Devices: XMerge.
Here is something that would allow to run wine on ARM: QEMU x86 Emulator.
Icons:
The core storage model for environment-wide data such as PIM data and user preferences is that of a relational database, implemented through the ubiquitous SQL (Structured Query Language).
We started to collect the database layouts used in GPE in the GpeDatabaseScheme wiki.
GPE supports the vCard and vCal standards for transferring address book and calendar information. We also plan to follow the IETF Calendaring and Scheduling standards. See also the OpenSync link below.