The local Blynk server requires a few steps to get running. When complete, you will have access to the admin panel for the local app server ready to take connections from the Android app and the Arduino hardware.

First make sure you have Java 8 running, in a terminal type

java -version

Download the server

server-0.18.2-SNAPSHOT.jar

Create a file 'server.properties' add these two lines and save it in the same folder as the server

admin.rootPath=/admin
allowed.administrator.ips=0.0.0.0/0

Run the server, from the terminal enter

java -jar server-0.18.2-SNAPSHOT.jar

Open a browser to

https://YOUR_LOCAL_IP:7443/admin

Ignore any ssl warnings in the browser and proceed. You should see the server dashboard.