PTT on touch

[Mr_wrong_0]

So I know sprint and nextel are compeleatly differant networks (cdma vs iden) but is there any program that gives a person the ability to use a PTT or chirp function between phones using the internet? Like if two people installed it and had unlimited data could they do PTT via the internet? I found one called iTalkie but it messed up my phone to the point that I had to do a hard reset.