Recommended Software

I've bought a ton of PDA software over the years, for both the Palm and Pocket PC platforms. You can really waste a lot of money on software. Even $20 here and there adds up, so I highly recommend you review what others say about a piece of software before loading it on your system, only to find out later a better product is available. Having said that, I have personally found the following software to be helpful.

For the Pocket PC:

Pocket Informant or Agenda Fusion (appointment, contact, and task management)
Pocket Mindmap (for developing mindmaps - this is a great planning and project management tool)
Resco Photo Viewer and/or xnView (the latter is freeware)
PhatNotes (an excellent note-keeping program that allows assigning user-definable categories to notes and linking notes to other files, and so forth)
eWallet (for keeping sensitive data secure and password-protected)
ListPro (excellent for managing lists and even projects, supporting multiple levels of indentation, color coding, and so forth)
Microsoft Reader, Palm Reader Pro, and MobiReader Pro (excellent for ebook reading)
PocketBible, OliveTree, or eSword
iSilo (for viewing websites offline and for viewing ebooks - excellent software)
Utilities: Calligrapher (for enhanced handwriting recognition and for great macro capability), Resco File Explorer, and MemMaid (for keeping the system clean). If you have a WM5 device, you will find MemMaid essential for fixing your "notification queue," which is what controls whether you receive an alarm for appointments. Without it to clean out all the duplicates and the trash entries, your alarms are not likely to work. For WM2003SE devices, the utilities ClearNotify, CheckNotification, and pTravelAlarm_WakeupTweak, address the issue of alarms not working.

A great place to find out more about expert opinions of Pocket PC software is the Smartphone and Pocket PC Magazine Best Software Awards 2006.

For the Palm:

Even though the Calendar, Task, Contacts, and Memo software that is built into the Palm PDAs work great without add-on software, you may want to consider adding DateBk5 or Agendus Pro - they add some useful functionality.
PalmReader Pro, MobiReader Pro, eWallet, ListPro, and iSilo (all listed above for Pocket PCs) are also available for Palms.
NoteStudio - an innovative application for managing notes in a wiki-style environment.
DayNotez (excellent journaling application)
HandyShopper (originally designed as a shopping aid, it has become one of the most used a popular checklist managers for the Palm platform, and is excellent for task and project management, AND, it's Free!)
ShadowPlan/Bonsai (either = great for project management - not designed for huge projects, but great for what most folks deal with)
TextPlus is an excellent tool for speeding text entry (the newer Palms, like the T5 or TX, must use a version of 5.8 or higher)
pEditPro is the Palm equivalent of the more popular Linux text editors. It has a learning curve to get the most out of it, but it offers powerful macros/scripting and many ways to speed up and simplify text entry. If you are heavy on text entry, this software is definitely worth checking out. In fact, I wrote the initial version of this site (back in 2001) using pEditPro and a Palm keyboard.
LifeBalance - Out of all the software I've listed here, this is the only one I haven't tried and that I do not use, but it gets a lot of positive press from its users, so it could well be worth trying.

For Windows:

OpenOffice.org 2.2 (Great, free replacement for MS Office)
Firefox Browser
ThunderBird (email)
ActiveSync 4.5
Google Pack (Google Earth, Google Desktop, Picasa, Google Toolbar for IE, Google Photos Screensaver, Norton Security Scan, Adobe Reader, Spyware Doctor Starter Edition, Mozilla Firefox with Google Toolbar ... all are free!)
MindManager 6 Pro
UltraEdit (a text editor on steroids ... great for its programming language support)/li>
System Mechanic
Windows Sysinternals
Diskeeper for disk defragmentation
Clean Disk Security for thorough hard drive cleaning (I've used with XP Pro but not sure if will work with Vista)