In this article, we curated a list of the best Kotlin starter kits that are available as of the time of this writing. Kotlin is the new cool kid in town: Google’s new programming language for coding up Android apps. It brings up a lot of value on the table, through amazing modern features such as higher order functions and lambdas, which were not supported in Java. With Kotlin, Google is shifting the paradigm towards functional programming, which can also be seen as a response to Apple adopting Swift.

Kotlin is extremely powerful and Android developers should adopt it as soon as possible. An effective way of ramping up on Kotlin is to download an existing free starter kit, to learn practically. By getting used to the Kotlin syntax and by making a few changes to existing open-source Kotlin templates, an Android developer can quickly incorporate the new language.

While working on our newly launched Dashboard iOS app template, we had to figure out how to add a padding to the placeholder of a UITextField control. It turned out there’s no native support for this design tweak, so we had to create our own subclass of UITextField.

Apple Pay and Google Pay can make mobile checkout faster, especially for commerce, marketplace, restaurant, delivery, booking, and service apps. Old React Native tutorials often mention Android Pay or abandoned Payment Request wrappers. For current production work, use the maintained payment SDK for your provider and keep privileged payment logic on your backend.

This guide focuses on Stripe's React Native SDK because it supports PaymentSheet and platform wallets through the same production payment flow.

There is no doubt that there are piles of money to be made in iOS app development. After all, Apple owned 15.2 percent of the global smartphone market last year. However, the worldwide popularity of the iPhone does not mean that an iOS app developer can simply do whatever he or she wants when creating iOS apps. iOS app developers must know these three pitfalls to avoid when trying to make money through iOS app development.

React Native payment integrations have changed a lot since early checkout packages wrapped a few native payment APIs. For production apps today, Stripe's React Native SDK and PaymentSheet are the safer default for card payments, Apple Pay, Google Pay, saved payment methods, and multi-method checkout.

The mobile app should never own payment secrets. It presents checkout, receives client-safe values, and shows status. A secure backend creates PaymentIntents, validates amounts, handles webhooks, and finalizes orders.

One of the most important aspects of designing a mobile app consists of colors. We’re introducing a Color Framework – Chameleon, which can be used by mobile developers to create iOS apps. It provides support for amazing flat colors, color gradients, complementary colors, colors from images, hex codes, and many other features. The framework can be used in both Swift and Objective-C and it’s open-source on Github.

As mobile app development becomes more dominant in the tech world, we can observe several design patterns emerging across the entire mobile app design ecosystem. One of these design subsystems is the skeleton views.

Many of our fully-coded iPhone app templates consist of a drawer menu navigation. This type of navigation usually is triggered by tapping on a menu button on the top left corner of the screen. Once clicked, the menu gets extended from the left side and takes over two-thirds of the screen. Here, the users can choose whatever option they want to navigate to. This type of app navigation is more popular in Android apps, but it gained some ground in the iOS realm as well, especially since concepts like Material design came out. People might also refer to this as hamburger menu navigation.

There are many use cases where you want your app to display collections of UI elements with flexible cell sizes, that render compactly on the screen, taking up as much space as possible. Unfortunately, achieving this in Swift is not straightforward and having collection views dealing with cells of different heights and widths can be tricky. In this tutorial, you'll be able to learn how you can create the layout pictured below (which is a shot of our WordPress iPhone App Template):

Accepting payments in your mobile app could be one of the core features your project supports, especially if you're selling physical products or services that are provided outside the app. For instance, any shopping app (e-commerce app) needs to have at least one way of accepting payments, within the app, so that users can buy products, directly with their phone and credit cards, and without too much overhead and friction.

For tech entrepreneurs, who own online businesses about news, building a news reader iOS app has never been more rewarding, in terms of growing and retaining their audiences. Empowering your readers with a mobile app for their favorite news website is powerful. It's hard to imagine a better way of increasing user retention. On top of that, with the latest tools that are available for building mobile apps, creating a presence in the App Store has never had a greater return on investment.

When it comes to mobile user experience, the field of psychology plays an important role by giving us relevant information about how we could design our mobile apps better, in order to create more value for our users. In this blog post, we list a number of mobile UX best practices that are extrapolated from research about the brain, the memory, motivation and visual system. By using some fundamental psychological principles, we can design mobile apps that are compatible with how people think and behave.