say I need to dial a number in Toronto, Canada (416) 000-0001. From different places, I dial different numbers: Canada: (416) 000-0001 US: 1 (416) 000-0001 China 00 1 (416) 000-0001 yes, adding a "+1" resolves all problems for calls in US and Canada, from US and Canada. However, calls to/from other countries require extra digits (country code, etc). My question is how to input these digits in my cell phone so that it knows when to use them (e.g. when I'm abroad) and when not to use them (e.g. when I'm home). Otherwise, I'd have to edit these numbers manually every time I 'm abroad.