Once you remove the app from your store > Apps section follow given steps to remove app from your store completely.

Step 1 : Go to Themes > Edit code.
Step 2 : Open Theme.liquid find a line of code given below :

<script src='//shopiapps.in/ultimate_scarcity_pro/widget/tscript.js'></script>

– Remove this added script from your theme.liquid file.
– Remove one more added snippet from at end of the file :

{% if template contains ‘product’ %}{% include ‘SpViewCount’ %}{% endif %}

Step 3 : Now open templates -> cart.liquid and remove below code :

{%include ‘sp_cartTimer’%}

Step 4: After complete above steps delete added snippet from snippet section:

Go to snippets -> open SpViewCount and click on the delete button.
Go to snippets -> open cartTimer and click on the delete button.

Now ultimate scarcity app has been removed!