Yesterday I found an interesting software “free sms“, developed by Zelfi. It is a J2ME application and it works with my Sony Ericsson K750i very well.
The shipment of one message costs me now only 3Ct, it is a good saving for me, because the standard price of one sms is about 19 Cent.
The cost of one message of “free sms” depends on costs of GPRS at your mobile operator, that’s why I would suggest you to check the prices of your mobile provider before you starting to use “free sms” software.
There is about 4 kilobyte of data will be transferred during the sending of one message. You could check how much 1 kilobyte of data costs for you and so you will understand how much money you could save with this software. As for me, it is very profitable, to use “free sms”, because it is much cheaper to use this applications than to send sms via my mobile provider and I have no problem with advertising too.

I’m afraid that the costs of data-transfer per GPRS + fee will be too high and that’s why many users will prefer such alternative transfer-possibilities as email, mms or “free sms” by Zelfi.

But if you like chat very much, you can also order “O2 surf and email pack” for only 5€ monthly and chat with your friends per WAP without any limitations.

“Toonel.net” is a free cross-platform open source software that gives you the possibility to lower your gprs-costs and increase speed of data transfer. The program works under Windows, Linux, Mac OS, Symbian OS, Windows Mobile and some others platforms and can compress the user traffic up to 50%.
P.S. On the screenshot you can see Pocket PC-version of the Toonel.net-Software, but without any data, it is because I have now some problems to setup the Internet-connection with my new mobile operator and that’s why I can’t say anything about the real efficiency of the software.