Google acquired Firebase in Oct. 2014. This gives Firebase a degree of trustworthiness in their service and future support since they are backed by such a large company.
The content is deployed immediately through the Firebase CLI. Once it's uploaded, the content is served immediately. If you have made a mistake, you don't need to re-upload a new version, through the Admin dashboard you can easily rollback to a previous version.
Kuzzle has no hosted version. In order to use it, you have to install it to a remote machine. This can be cost-effective but it also adds overhead because you will have to take care of the hosting and backend infrastructure yourself.
Since you host Hoodie on your own infrastructure, you only get to pay hosting costs, compared to other hosted solutions where you also have to pay additional money to compensate for the reduced overhead of having to maintain your own infrastructure and installation.
The current Unity SDK is several years old and doesn't seem to work with recent Unity Editors (2021.1 as of this writing). The task based infrastructure is baked into a DLL and thus not adjustable. You might be able to get it to work through NuGet packages, though.
Google App Engine is very easy to use. All you need to do is install the SDK (which in itself is easy as well, and the documentation is very heplful) and run the command needed depending on the type of project to deploy it.
For example, to deploy a golang application, you run golang deploy inside the project folder and it will be automatically deployed.
Google App Engine integrates with Google's CDN out of the box and it distributes your application's assets through that, increasing loading speed considerably.
Setting up a backend for an app with Parse is very easy and takes minutes. All you have to do is sign up and through their graphical interface follow all the steps, which boils down to creating tables and identifying the type of data that is being stored.
Then you download the library, integrate it with your app and initialize the process with one single line.
Parse has excellent documentation. Everything is thoroughly explained and all parts of the documentation are complete. It's actually very helpful for both beginners and advanced users alike.
User registration with Parse is pretty good and usually works without any problems. It's also very easy to use, you simply pass the username, password, email, etc. to the required method and register a callback that returns whether the registration was a success or a failure.
Same thing is done for login and logout as well.
There have been several reports that it's not unlikely for Parse to go down several minutes almost every day. This can be very frustrating for both developers and users who are using apps built on Parse.
I'm a no coder - this saves me from not only the task of actual coding but also tech jargons that sometimes cause confusion. Now I know fully what is happening with the app for my business and not needing a tech personel to always "translate" for me.