Sample Code:
<aura:component implements=”force:appHostable” >
<aura:attribute name=”oppty”
type=”Opportunity”
default=”{ ‘sobjectType’: ‘Opportunity’}”/>
<div class=”slds-box slds-theme_default”>
Account : <force:inputField value=”{!v.oppty.AccountId}”/>
</div>
</aura:component>
Output: