Sounds interesting, but it appears to be available only in the US, and the international roaming only works for 90 days, so I don't think it really qualifies for "without bothering about new contracts, moving cities or country borders"
> Important: The Google Fi Terms of Service require you to activate and use Google Fi service mainly in the United States (not including territories) for at least one day before using Google Fi abroad. If the majority of your usage occurs outside of the United States over a consecutive 90-day period, we will suspend your international data. Learn more at our Help Center.
