According to relevant information, the squirrel book delivery app closed down because of "lack of money". The squirrel book delivery app is a software that is biased towards public welfare. There is no money transaction here, only a group of lovely people give books to each other and spread positive energy. You can also ask for books here and get the books you want. You only need to pay the postage in this process.

This entry point is very suitable for squirrels to deliver books. Although books are given away for free, those who get them need to pay postage, which will undoubtedly screen out those who really need them. Squirrels send books by selling application quotas to earn income, and the profit model is relatively simple.