Try with this HTML to solve Android issue:
<ion-header>
<ion-navbar hideBackButton color="pastelblue">
<ion-buttons start>
<button ion-button icon-only>
<ion-icon name="swap"></ion-icon>
</button>
</ion-buttons>
<ion-title>
myTasks
</ion-title>
<ion-buttons end>
<button ion-button icon-only end>
<ion-icon name="add-circle"></ion-icon>
</button>
</ion-buttons>
</ion-navbar>
</ion-header>
<ion-content padding>
</ion-content>
iOS issue is duplicated: