The android device data transfer was a long question, i think it's very convenient to use a mobile phone file transfer and backup app to help. Try Coolmuster Android Assistant, just few simple steps to transfer everything from your phone to computer. backup contacts android
To transfer data from android to android, i think it's more convenient to use a mobile transfer app. You just need to connect your two phones to computer at the same time and start the app to transfer data, here you should set old android in the source position and new android in the desition position.