I was planning to use ion-tabs as a decorative element in my application, w/o its router integration. However, putting it on the same page with other elements was breaking those elements. For example ion-select stopped working completely – no dropdown was available.
I found the following solution: the ion-tabs block should be placed inside ion-footer, like this:
<ion-content>
Any code will work here, for example ion-select.
</ion-content>
<ion-footer class="ion-no-border">
<ion-toolbar>
<ion-tabs>
<ion-tab-button>
...
</ion-tab-button>
</ion-tabs>
</ion-toolbar>
</ion-footer>