How to submit/retrieve user data—do I need a server?

Hey there—I’m a beginning coder and this is my first post here. This is not one of the FCC projects.

I wrote a little web app to let me and my roommate monitor when our dog was last walked and uploaded it to github pages.

It only needs to save and retrieve the day, time and name of the person who last walked the dog. Right now the app is saving this data locally but I need to learn how to get it on some kind of server so that my roommate and I can use it on mobile.

My questions are:

  1. do I need to set up and pay for some kind of server service (I feel like this might be overkill for such a little project) or can I host the necessary files on Google Drive or Drop Box? What’s the easiest and cheapest way for me to do this?

  2. What new skills/languages should I start learning to get this simple thing done? PHP? JSON? SQL? I really don’t know.

I’ve been trying to figure this out on my own for a few days. I’m guessing that someone here can answer this easily. Thanks for your help

You can set up a simple express server using node.js --> free
You can set up a small mongodDB database (<500mb) on mLab --> free
And host it on Heroku --> free (though it goes to sleeps on every half an hour of inactivity and takes 30 secs to wake up) (edit: you can also host it on glitch , it too will go to sleep however)

Your dog walking client side form would simply send a POST to your express server, server time-stamps the request and creates a new document in the database , and whenever anyone loads the app it does a GET request to the express server which goes back to the database and gets the last person who walked the dog. You should be done with the back-end in less than 50 lines, if that.
This would actually would be a good exercise to get familiar with the back end side of things.
Feel free to post questions here, plenty of people can help you out here.

thank you so much for your help! Much appreciated!