I am about to start the first Web App (Building a Vote App).
I followed the tutorial about c9.io and clementine to set development environment.
I checked where people who finished lastly the project hosted them. Most of them hosted them in Heroku, but I found some
that did it in Glitch.
Which one is recommendable?
I would recommend Heroku. Really fast and simple solution. 
I paid around $3.80 a mouth for a 2 cores 1gb ram VPS in Florida, and there are even better deals around. Check lowendbox. Of course using big name cloud platform like AWS and Heroku get your some barking in your resume, but they’re very expensive. Also, VPS needs command line setups.
Well then use digitalocean if you want some VPS
Heroku and AWS have free tiers that meet the majority of use cases for small developer websites. Their pricing isn’t expensive unless you are some huge business with lots of traffic who can afford it.
DigitalOcean makes stuff really simple but are lacking in features.
Let’s discuss the free tier options out there. Anyone has extra info please share with us.
From what I known,
Google Cloud and AWS all offer one year free up time of an instant(They call it dyno, EC2, whatever. It’s Linux; It’s VPS). After one year, if you decide to stay with them, you have to pay at a much higher price comparing with some bare bone VPS offering out there. If you decide to leave, you have to migrate all your things on there. Some of things you have done there maybe using their platform specified services(e.g. their DB) that have to do extra works to get it going on an open source regular solution(MySQL, Mongo).
Heroku gives a true life long free tier. However, They put it into “sleep mode”, which take a 5-10 seconds to re-boost. Unacceptable in my book for your resume projects. Nobody wait that long for a website to load. Even worst if it’s a recruiter they just assumed you’re too much of a noob that can’t get a site working.