Centering elements (other than texts) inside a <ion-col></ion-col> is painful. Apply the following CSS in your respective component level scss or global theme to align items centrally.

center-align.scss

.center{
  display: -webkit-box;
    display: -moz-box;
    display: -ms-flexbox;
    display: -webkit-flex;
    display: flex;
    -webkit-box-direction: normal;
    -moz-box-direction: normal;
    -webkit-box-orient: horizontal;
    -moz-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;
    -webkit-flex-wrap: nowrap;
    -ms-flex-wrap: nowrap;
    flex-wrap: nowrap;
    -webkit-box-pack: center;
    -moz-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;
    -webkit-align-content: stretch;
    -ms-flex-line-pack: stretch;
    align-content: stretch;
    -webkit-box-align: center;
    -moz-box-align: center;
    -webkit-align-items: center;
    -ms-flex-align: center;
    align-items: center;
};

sample.html

<ion-row>
   <ion-col class="center">
      <!-- your element here -->
   </ion-col>
</ion-row>

Best solution. Thanks!

Glad to know that it came to your use.