MetroTalk (Version 3.1.1)
apoelin
$1.49 / Free
After I initially received my Nokia Lumia 920, AT&T screwed up when transferring both my unlimited data and unlimited messaging plan. Since customer support was worthless in helping me, I had to go into an AT&T store to get it sorted out. During the few days of downtime, I was able to use the phone over wifi and decided to try out some text messaging apps. One of the criteria was being able to text others without the recipient having the same app. The choices were limited and I eventually settled on using Google Voice as the main client.