In my opinion, just get Native Messages and Phone app and Use SMS GV Extention and Phone extention to make calls/sms texts using a google acc. via wifi and use a tethered android and use it as a mobile router :0
Looks well thought out, but might be laggy at first. And Comments to the videos lead me to confirm it's free but w/ in-app purchases
And BTW this is made by the same company that made Inotia 1/2 (Probably made this to compete with Zenonia 2)