This can be changed easily from the server side code: views/SingleItem.htm line 29:

<a href='https://play.google.com/store/apps/details?id=com.neurondigital.recipeapp&pcampaignid=MKT-Other-global-all-co-prtnr-py-PartBadge-Mar2515-1'>
<img class="download-btn" alt='Get it on Google Play' src='https://play.google.com/intl/en_us/badges/images/generic/en_badge_web_generic.png'/>
</a>