The free extra SIM project enables Google to see how customers use phones and tablets without access to a mobile voice network.
Part of Google's mission is transitioning mobile phones off SMS and MMS and onto Rich Communication Services, or RCS. (Google's communications chief, Nick Fox, tweeted last month that Google is working to bring RCS to Project Fi.)
The second part is to midwife the birth of the post-phone world, starting with Voice over Long-Term Evolution (VoLTE).
These transitions might be inevitable, even without Google's involvement. But they also might not.
Everything about telephony is complicated. Project Fi enables Google to try and test and experiment, easing Fi users gently and slowly through the touch-and-go transition to a world that doesn't use the mobile voice networks.
The biggest event in the post-phone transition is VoLTE.
VoLTE is a gateway drug to the post-phone world
In January, some Project Fi users noticed that their calls were being handled by VoLTE. So in February, Google quietly announced that it had started to test VoLTE "with a subset of Project Fi users."
VoLTE is a highly optimized and much better performing approach than regular VoIP over LTE. And, for that matter, it offers better quality calls than today's voice network calls.
Another huge benefit is that VoLTE enables video streaming, file transfer and other features directly from a phone's native dialer. VoLTE is also the solution to the current divide among US carriers between CDMA and GSM networks.
Let's be clear about what VoLTE on Fi represents. Right now, VoIP over Wi-Fi is the alternative to using the wireless voice phone networks. VoLTE is becoming another alternative, using the carriers' data networks instead of phone networks. (Note: Google is not charging users for data used via VoLTE.)
With Project Fi, Google can tweak and experiment to figure out the best way to gradually get more users making and taking calls via Wi-Fi and VoLTE, and fewer via the wireless voice networks.
Interestingly, the whole Google Fi handoff scheme works much better with VoLTE than with the voice network. The reason is that while Fi can hand-off a call from WiFi to cellular, it can't hand it back from cellular to WiFi. So if you're on a call and enter a building with strong WiFi but weak cellular, the call will drop.
However, with data, the hand-off works in both directions. And since VoLTE is on the data network, you can go from WiFi to mobile broadband and back again without dropping the call.
The Future of Fi is IP telephony for enterprises
Within two years, I believe Project Fi will be available to companies of all sizes, including enterprises, as a core part of G Suite.
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