Must Have Apps
From S60 Getting Started here are a selection of must have apps for S60 phones.
Gravity - the Twitter/Identica client for S60 - AAS review WirelessIRC - IRC for S60 1st, 2nd, and 3rd edition phones - AAS review mIRGGI - IRC for S60 2nd and 3rd Edition phones Opera - Web browser FExplorer - File Explorer Remote Professional - View and control your phone from your PC, superb for productivity, app testing and presentations AutoLock - Automatic keypad lock Agile Messenger - Instant Messaging, MSN, Yahoo, ICQ, AOL et al, sadly the latest version no longer supports Jabber nor is free PuTTY - SSH client All About Symbian's - 3rd edition essentials More software And yet more software Gadget17's extensive list of S60 Freeware Symbian-Freeware.com rather sparse list currently The Symbian Wiki's list of Series 60 Freeware Symtopia S60 3rd edition and UIQ 3.0 software directory Virgin Radio's 3G Radio Player is worth a play if you're on a flat rate GPRS or 3G data tariff, as contrary to the naming it does work over GPRS not just 3G, although it only works on Series 60 2.x devices (so no joy for Nokia 7650, Nokia 3650, Nokia N-Gage, Sendo X, Sendo X2, or Siemens SX1 owners). Profimail Papyrus is a great replacement for the default calendar. Truphone - VoIP solution for Wifi equipped S60 phones. N95 Blog - 25 Must have N95 apps - many also apply to other phones
ReadM, WebViewer, Picoblogger, Quickoffice, Pocket Counter, Azure, Helix Player, Sportstracker, Nokia Chat, and Agilemail need to be added.
Snakes and Doom are ideal free N-Gage games
Interesting Apps has a collection of interesting looking S60 apps, but I'm less sure as to whether they should be "Must Haves".