I am considering implementing Lightning for Outlook for a few clients so they can use the Salesforce Console within Outlook. Is it ready to use on mobile devices yet? iPhone?

I am working on the Developer Beginner trailhead. One of the exercises is below:

-----------
Contact jane = new Contact(FirstName='Jane',
                         LastName='Smith',
                         Email='jane.smith@example.com',
                         Description='Contact of the day');
insert jane;

// 1. Upsert using an idLookup field
// Create a second sObject variable.
// This variable doesn’t have any ID set.
Contact jane2 = new Contact(FirstName='Jane',
                         LastName='Smith',  
                         Email='jane.smith@example.com',
                         Description='Prefers to be contacted by email.');
// Upsert the contact by using the idLookup field for matching.
upsert jane2 Contact.fields.Email;

// Verify that the contact has been updated
System.assertEquals('Prefers to be contacted by email.',
                   [SELECT Description FROM Contact WHERE Id=:jane.Id].Description);
-------------
I understand the gist of the code, but cannot find a reference in the Apex documentation about the syntax within the bolded lines. Would someone break down each piece of this code for me? In particular why does the [Select...].Description phrase require the .Description?

My dilemma has been that I have a great deal of experience with programming, but not with Java. So much of the material I'm finding assumes knowledge of Jave syntax.

I am about to rip my hair out, I have searched all the questions and answers I could find in the communit, and still can't get this to work. I think it is in the Apex Method, I am not sure what the code is there. and have not been able to find anything to reference to figure it out. Here is my code:

<apex:page controller="NewCaseListController" showHeader="false">
    <apex:form >
        <apex:pageBlock title="Cases List" id="cases_list">            
            <apex:pageBlockTable value="{! Cases }" var="cs">
                    <apex:outputLink value="/!{cs.id}">{!cs.id}</apex:outputLink>
                          <apex:repeat value="{!Cases}" var="case" id="theRepeat">
                         </apex:repeat>
                <apex:column value="{! cs.CaseNumber }"/>
                <apex:column value="{! cs.id }"/>
                <apex:column value="{! cs.Status='New'}"/>
            </apex:pageBlockTable>
        </apex:pageBlock>
    </apex:form>
</apex:page>


Please help me. 
Thank you,