These were Java-applets for Symbian OS, widely avaible and pretty easy to code.
You don't need a wide spectrum to control TVs and alike (a carrier frequency of 36kHz and 38kHz is enough to control about 99% of the devices), the range was ok. The 6600 had about 3m range.
Generally: the older the mobile phone, the stronger the IrDA :-)http://www.novii.tv
< there you can buy some of the remote control applications.