For iPhone, APN needs to be manually edited if you use Google Fi outside of U.S.. Go to settings, Cellular, Cellular Data, Cellular Data Options, turn on Data Roaming, also Cellular Data Network, change APN to h2g2 for top Cellular Data section and add h2g2 for bottom LTE Setup (optional) section. Change APN to h2g2-t if you need phone to be a hotspot (may work within U.S. and may not work outside U.S.).
For android phone, go to settings, Mobile networks, Access Point Names, click + sign on top right, Edit access point, Name: Google Fi, APN: h2g2. Change APN to h2g2-t if you need phone to be a hotspot (may or may not work depending on phones and locations).
Settings to make phone calls and texting with Hangouts app
For iPhone just download Hangouts app
Hangouts iPhone Settings
Settings / Answer on lock screen (switch to on)
Settings / Phone number / Incoming phone calls (switch to on)
Settings / Phone number / Messages (switch to on)
For android phone you need to download both Hangouts app and Hangouts Dialer app to call and text. Edit settings in Hangouts app, click Account
Incoming phone calls (switch to on)
Messages (switch to on)
Incoming calls, Vibrate and play sound, Sound (choose a Ringtone)
From your computer GoogleVoice account
Settings / Calls, Forward calls to linked numbers (uncheck)
Settings / Calls, Screen calls (switch to off)
How to track cellular data usage
iPhone Go to settings, cellular, under cellular data there is a Current Period, that number is how much cellular data has been used since last reset. Scroll down all the way, press Reset Statistics and cellular data count will become zero. Reset at the beginning of the billing cycle.
Android Go to settings, Network & Internet, Data usage, Cellular data counters, click upper right corner 3 dots, Reset data. Reset at the beginning of the billing cycle.
Troubleshooting for not connecting to a local wireless carrier
Tip 1: Manually choose a local carrier that has roaming agreement with Google Fi. Go to settings, Carrier, Turn off Automatic, choose one carrier from the list. You can try different one until one works.
Tip 2: Go to settings, Cellular, and toggle Cellular data off and back on. If that doesn’t work immediately, turn on Airplane Mode and then off. If that still doesn’t work, power off and back on.
Tip 3: Even for iPhone, APN may need to be manually added. Go to settings, Cellular, Cellular Data, Cellular Data Options, Cellular Data Network, add APN h2g2 for both top and bottom sections.
Tip 4: Use Fi repair service if not connect. Dial repair code: ##34963##
Let the phone "repair" for 10 mins, looked stuck, rebooted and got call and data access working.
List of countries that have fast LTE coverage, tested by group members
China (in Hong Kong use 3, in China use 中国联通 instead of 中国移动 if possible), UK, France, Spain, Germany (Vodafone), Switzerland, Romania (Telekom.RO), Bulgaria (Telenor BG), Macedonia (T-Mobile.Ma), Albania (Telekom.Al), Croatia (HT HR), Bosnia (HT HR), Slovenia (Mobitel), Canada (Telus or Bell),Turkey (Turkcell), Japan (Softbank or Docomo), Colombia (TIGO), Peru (Claro or Movestar),
List of countries that have slow or no coverage, tested by group members