Good Hunt @honourmaus

Note: This is just ”My Personal Opinion & Assessment”, not intended to “Judge” the reviews you have made.

Pros:

• Idea / Innovation
  From what I see on the Googleplay page, the idea of Bitcoin Calculator is pretty simple. It's like a conversion calculator calculator between BTC to various local currencies (fiat).
• Design / UI / Spec
  The Bitcoin Calculator design is simple, it can be used by anyone.
• Features / Advantages / Benefits
  Its features are limited to BTC conversion to fiat currency. Actually this is less useful when we can convert it easily on the web page.
• Price
  It's free to use. No annoying ads.

Cons:
Unfortunately, its function is too limited. Maybe if there are other additional features, this could be a cooler product.