Imo this app is completely useless and you are better off locking yourself in a room with a clock. The whole forest aspect is a scam and all the trees are super tedious to obtain depending on one's study needs. And to pay premium to plnt real trees is a feel good way to buyg their product and it takes 3 days of studying to plant a tree. Yes I paid premium. I use ecosia and I planted over 400 trees web surfing. The sounds are useless too as you can get tons of sounds on other app effortlessly.