7.EthereuminAndroid

    
       How to build Android Dapp on top of Ethereum


  1. Web3j is one of the library that helps in building Android Dapps
  2. It helps interacting with the blockchain at the same time provide wallet support.
  3. Also has feature for accessing the private wallet file from ur phone memory or can enter public privaye key or with help of the mnemonic.
  4. Web3j is the java version of Web3 and has all the features provided by web3.
  5. Creation of smart contract wrapper to intereact with smart contract, access the account info and many more.
  
  To use Web3j :
  
  Add web3j to the depedencies as given in the documentation and u r good to go.
  Adding bouncy Castle Provider is at the same time necesssary, the reason is even though Android implements bouncy castle already but it does not have ECDSA implemented fully which is required for wallet
  generation/ mainly for KeyPair generation
  For smart contract interaction you need the abi which is generated when you compile the smart contract.