Macbook air support

We are running CRM 2015.    We have added a MacBook Air   running OS X  10.10.5.     The problem is that CRM sees this as a phone not as a computer so it shows the CRM mobile screens  rather than the standard CRM screens that our other  computers see.    We have tried it on three different browsers  (safari, firefox, and chrome) all give the same result.   They push directly to CRM Mobile.....  Any ideas on what we need to do so that the browser runs the regular computer screen?

thanks