- The first prerequisite is to have a browser like Google Chrome, Firefox or Brave. On your smarthone you can use Metamask Mobile.
- The browser must have the Metamask extension installed, which allows you to interact with the blockchain, more details here: https://metamask.io/
A nice video tutorial about Metamask can be found here, remember to set it to the Rinkeby network.
Note: Metamask extension is only needed for data insertion. Everyone can read the data and explore histories with a simple browser from any device.