App Signup: Mobile Number VS Email Address

Hi,

What is the best way to get your users to signup on your app (mobile only app). Should you get them to signup with the usual email address method OR is it better to just allow them to signup with their mobile number. I can’t find any reputable articles online that cover this.

Can anyone tell me the advantages and disadvantages of both:

01 - Signing Up With Email Address (Advantages and Disadvantages)

02 - Signup With Mobile Number (Advantages and Disadvantages)

Thanks in advance for your help.