Unfortunately no, I didn't find any other free ones at least that use Wi-Fi. I have searched all around the web and no luck,
The only ones that do work with Wi-Fi but you have to buy them are IM+ and BeeJive
.
If you want search them out, they have a 10 or 30 day trial so you can test them out.
I personally use Palringo and even though the usage of it is a bit not friendly, its the only one that works for me.
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