From the app's site: "Whenever you want to focus, plant a tree. The tree will grow in the following time. The tree will be killed if you leave this app." So

From the app's site: "Whenever you want to focus, plant a tree. The tree will grow in the following time. The tree will be killed if you leave this app." So probably, yeah. I assume there is some point at which the tree won't be killed since it goes on to talk about keeping a forest of trees representing stretches of time not using your phone to do anything other than run this app - hitting up its app store page describes it as a pomodoro timer, so about 25min gets you a tree. My inner paranoid says "wow, what a great way to get people to help you mine cryptocurrency" but I will choose to assume that they're happy with the money they're making by selling it for two bucks, plus the occasional "sunshine elixir" IAP.