You are authenticating your Expo app users with email and password using Firebase. It works great but marketing funnels seem to indicate that users quit the app at the sign up screen. Looks like offering social sign options will help mitigate that problem, so says the marketing department, and you now want to add Apple sign-in and Google sign-in to your app. This is how to do it in February 2021!

To follow along with this story you need to meet this two requirements. You can check how to do so in Email authentication in React Native apps using Firebase:


I choose React Native to develop mobile apps because it simplifies development so I want user authentication to be as simple as possible too. Firebase provides backend services and client side SDKs for authentication purposes and it’s built by Google. That’s a match! This is how to authenticate users with email and password in React Native apps using Firebase Authentication.

Why Firebase Authentication?

User authentication has become a mandatory requirement for most applications and developers have to implement it again and again. It usually consists of the same set of core functionalities (e.g sign up, email verification, sign in, reset password, maximum number…


So you heard that Apple is rather picky when it comes to accepting apps in App Store. And indeed, Apple does make it much harder than Google when it comes to publishing apps. This doesn’t mean it’s impossible however. All you will need is patience and, if possible, following the advice of somebody who has done it before. This is what it looks like to upload an iOS to App Store in January 2021.

Both App Store and Play Store require you to purchase a developer license. While Play Store’s license is cheap ($25) and lasts forever, Apple’s one is…


So you just had that amazing idea for a killer mobile app. You know how to develop it and you have the motivation but you are not sure how hard it’s gonna be to get it published on Play Store. Or maybe you don’t have the idea yet, but still you wonder about how publishing a mobile app works. You came to the right article. This is what it looks like to upload an Android app to Play Store in January 2021.

Both App Store and Play Store require you to purchase a developer license. While Play Store’s license is…


Need somewhere to host your WordPress site? Google Cloud Platform makes it specially easy, providing preconfigured virtual machines. Your site will be up and running in under an hour, using your custom domain, accepting HTTPS traffic and being able to send emails from contact forms.

Before reading the article be aware that there are many alternatives when it comes to hosting WordPress pages. Having WordPress in GCP is not the cheapest one by far: around 22€/month for a small instance based on my last invoice. If you don’t need a dedicated virtual machine consider using other hosting solutions. …


Web developers owe a great deal to npm JavaScript libraries. npm packages resolve common web problems in elegant ways, are free to use, rock solid (potentially tested by thousands of users) and save development efforts. No doubt npm makes our lives easier but… who are those anonymous open source heroes? Well, you can be the next one!

Why creating a Javascript library?

  • To help yourself: How many times did you start implementing a feature in a project and suddenly remember about a time you did something similar in another project? Instead of copy and pasting the code from one repository to the other you can…

So you have just finished your splendid new node.js express app, it runs smoothly in your local environment and you are ready to make it available to the users who are eagerly awaiting for the release. The question now is… where to deploy it? Search no more! Google Cloud Platform is the place you’ve been looking for. Seamlessly deploy your app with a single command and let Google handle the scaling your app needs according to the users traffic.

The conventional way

Before the appearance of cloud infrastructure providers (e.g. Google Cloud, Amazon Web Services, Microsoft Azure, etc.), the usual deployment process consisted…


Build a wheel of fortune in CSS… is that even possible!? I had never thought about it until I met a group of entrepreneurs who were building a savings application based on video games. They were using React Native and a couple of graphics libraries which, in my opinion, seemed to be too much overhead for just a roulette. I immediately started to dig in the internet and I found a way to implement it in pure CSS3 and HTML. The CSS property that makes it possible? Meet your new best friend: linear-gradient 🕶️

So the problem is simple; a…


When building a web on my own I generally face two challenges: what to put in it and how to put it. Usually the urge of getting the job done pushes me to start developing after visualizing the global picture, and I don’t spend enough time trying to solve those challenges properly. As a consequence of this haste, I sometimes feel my web sites are lacking something… but what exactly? Here are the bad decisions I made while developing my old website and how I approached them on the new version of my web page.

Web format

I created my web page…


My mother has always been a fervent newspaper reader and she is in the habit of solving the puzzles that come in the last pages. Between those puzzles you can always find a game called sudoku. Two actually; a reasonably difficult one and an evil one. So she was in the middle of filling the first sudoku when I interrupted her. I don’t remember what for but I do remember that we talked about sudoku and it was the difference between the two sudoku levels that caught my attention.

Carles Capellas

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