Funny description: "A variety of formats are supported, ..."
Phone Number
The telephone number that will be displayed in the phone dialer
when the activity is selected. A variety of formats are supported,
however we recommend you include the country code such as:
1-212-555-1234.
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This is a very funny description, "variety" means (many) different formats, ... WHICH ones?
The recommended one is the only one I strongly suggest NOT to use!!!!
The International phone number starts with a "+" to avoid phone numbers which omit country code and area code.
E.g., Taiwan has the country code 886, to use 1-886- .... would dial a local number 1886 ... and not as expected Taiwan, ...
;-)