How to iterate map in Salesforce Lightning Component?

<aura:component controller="MyMapClass">
<aura:handler name="init" value="{!this}" action="{!c.doInit}"/>
<aura:attribute name="myMap" type="Map" />
{!v.myMap.key1} <br/>
{!v.myMap.key2}
</aura:component>
({
doInit: function(component, event, helper) {

var action = component.get('c.getMyMap');

action.setCallback(this,function(response){
alert(JSON.stringify(response.getReturnValue()));
component.set('v.myMap',response.getReturnValue());
});
$A.enqueueAction(action);
}
})
public class MyMapClass {
@AuraEnabled
public static map<String,String> getMyMap(){
Map<String,String> Mymap = new Map<String,String>();
Mymap.put('key1','apple');
Mymap.put('key2','mango');
return Mymap;
}
}
here is a simple example to use map in lightning component and use @AuraEnabled in you apex class method
component