I am trying to build a python application that reads AND writes data to a file online that other instances of the application have access to. I know I could use sockets with a dedicated server, but I don't have one. Is there any service that does this, or should I get a server?
Thanks
There are quite a few ways one can imagine handling this. However, the right solution is almost certainly setting up a database. AWS offers free services below a certain tier of usage. Look there if this is a small personal project.
Since you are using python, you should be using sqlalchemy to define a model and interact with your persistent data. You can setup such a database on an ec2 instance for free if you keep it small enough. RDS makes database management easier, but I'm not sure there is a free tier for it.
Python Data Acquisition Without Server