As we all knows default to ionic platform, which means that it will try to behave according to the platform that they are built on. In the case of tabs icons, for iOS the default is to display on bottom, and Android on top, in case you wan to display in bottom for each then you have to so something  like this-

To place the ionicFramework tabs at the bottom of the screen for android devices just open your

1. app.js file,
2. under angular.module
3. add the following lines of code-

.config(function($ionicConfigProvider) {
    $ionicConfigProvider.tabs.position('bottom');
})

It will display tabs in bottom.
Hope it will work out.
for more we can see 
http://stackoverflow.com/questions/27874855/how-to-place-ionic-tabs-at-the-bottom-of-the-screen

Have a nice Day!!!