In the manual Sony says: Charge it often. The backlight consumes a lot of power, so I charge mine every evening. If I forgot to do so, the next day I'm running low of power in the afternoon. My daily use is about 2 - 3 hours with backlight set at 50 - 75 % and the battery-consumption is about 50 % a day. To connect it with a calendar (I assume Outlook or similar stuff) you need to install the Palm-Desktop or Intellisync on your husbands computer. If you intend to sync a PDA with more than one computer / calendar you should know, that this might cause problems.