Requirements
You need to have mobilelocker-tracking v3.0.70 or later for this to work.
You need to have an active CRM connector (Salesforce, Veeva CRM, or Synergistix CATS). Contact Mobile Locker support if you're not sure about this.
You need to have the Customer picker turned on from Team Settings.
You can open the Customer Picker from your JavaScript code.
mobilelocker.openCustomerPicker();