In my opinion, the purpose of all software applications that have been created so far, are being and will be developed should primarily be to make humans' day-to-day activities easier to fulfill. Humans are the most valuable creations, and software applications are great tools that at least could be used by them.
Nowadays, almost every software product exchanges data with at least one other peer software product, which results in huge amounts of data flowing among them. Usually, a request from one product to another needs to pass a set of preconditions before it is considered acceptable and trustworthy.