I am trying to find best way to validate a mobile number with in a country.
Currently my understanding is: User can enter whatever format they want in mobile numbers and its a waste of time and energy to validate it against a set of regular expressions.
My application is not a critical one like banking application and if the user is entering an invalid mobile number, it is at his own risk to get updates (like activate account/ do something with the application)
So I think the best way is to check for mobile number length and whether all are digits.
I want to know the best way forward and is there any good resource (non-scattered) to get all mobile number length validations based on a country code?