We've used Celsius since 1978. Some older people still use Fahrenheit, but not many.
Even in my part of southern Canada it can get down to -40 (which is the same in either scale
) but the summers are quite warm, even hot by British standards. Temperatures in the high 30s are not that unusual in midsummer.
CA: SaskTel, Wind postpaid; Rogers, Bell postpaid iPad flex plans; US: T-Mobile postpaid data, prepaid voice; PureTalk (AT&T MVNO) prepaid voice/data; AT&T prepaid iPad plan
Hardware: Too much but notably iPhone 5, iPad Mini Retina LTE, Moto G LTE (N.A. version), iPhone 4. All unlocked.