There are 4 screens:
First one is main screen with the dark blue background and an open envelope on it. That envelope shows in the button direction. There is a button on in and it should be pressed for getting random email address,without choosing tmails,disbox,moakt.ws...everything is random,just one click.That is the first step. On the top left corner there is a language button.
On the second screen, you got your email address and you can use it for a just 1 hour. There are some main function in free version like delete or copy and you can get edit button in paid version. Also in paid version you can choose how long your email address last for 2 hours, 3 hours...
Last two screens are classic inbox and message screens. There are some main features like search messages,notifications and delete messages. In paid version maybe you can get reply and forward button for messages.
I have used free unsplash photos and paid version of lineicons.