Dealing with phone numbers in contact book

If you are building an app that uses the user’s contact book then their certain gotchas to avoid. Telephone country codes are prefix-free If a country has a country code β€œ+91”, then no other country will get a country code like β€œ+912” or β€œ+913”. This scheme ensures that numbers are inherently unambiguous. Telephone numbers can have multiple representations Since most people don’t dial internationally, telecom systems implicitly assume a domestic call....