The hangouts app was actually sick. You could connect to Google voice and your actual phone number allowing you to:

• place phone calls from voice on your computer or phone
• place phone calls from your actual number on your phone
• send text messages from voice on your computer or phone
• send text messages from your actual number on your phone (and possibly computer)
• send ims from your computer or phone

It was available within gmail or on its own dedicated site, and it automatically collated conversations regardless of send medium.

It made communication free and easy regardless of what device I was using–then they rebranded it and made it IM only–then they killed it.