Blockchain Safety & Transparency: The AppCoins Solution

Authentication on Back-End: Immutable, Reliable and Secure

  • \x19Ethereum Signed Message:\n: predefined message by the standard
  • 42: length of the message (the wallet address in our case)
  • 0x20286E1865b26dbC18393322D94cCaEB1A5983B6: the message (the wallet address in our case)

Merkle Tree: How Transaction Verification Works

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The data we consider relevant is:

  • Amount in Wei — the purchase value in Wei (ethereum unit)
  • Address — buyer
  • Dev — owner of the app where the purchase was made
  • Store — android app store associated with the app that made the purchase
  • Oem — the android device manufacturer
  • Package_name — application identifier
  • Sku — purchased item identifier
  • Timestamp as %Y-%m-%dT%H:%M:%S.%f — purchase time stamp
  • Country — where the purchase was made

Then we carefully generate the hashes between that data in the following order:



The python code used to reproduce the transaction id is the following:

Image Source

Address Proxy: Reliability and Updatability in One Contract



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AppCoins Official

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