Wow, didn't know you can hide resources from the library, nice tip.

Google Play Core library version 1.8.0 brings a long-awaited feature: native in-app review dialog. I added it to the latest version of Settle Up and I’m very satisfied with it — it instantly boosted our ratings and the integration was very simple. Goodbye annoying custom dialogs asking for a review.

When to ask for a review?

This is the hardest part of the integration. You have to identify a place where to ask for the review. The documentation states:

Trigger the in-app review flow after a user has experienced enough of your app or game to provide useful feedback.

Do not prompt the user excessively for…

We have been working hard on the new Settle Up for iOS and it’s finally here. It brings the long-awaited feature parity with Android and Windows versions. Now your friends with iPhones are not limited in using Settle Up.

The app is free to download

Up until now, Settle Up cost $1.99 on iOS, while the app on Android has always been free. We heard you loud and clear that friends on Android can use the app freely while iOS friends had to pay up front. This different monetization was due to historical reasons, but now it’s finally unified. …

Navigation library from Jetpack has recently reached RC1 and all Android developers should start considering it for new apps. I’m responsible for app architecture of Air Bank Germany — a new mobile-first German bank. Our app has a multi-module, single-activity architecture with ViewModels from Architecture Components. Integrating Navigation Component was a logical step, but it wasn’t without a few gotchas. In this blogpost, I want to share how we solved them. It’s a more advanced post, so I assume the readers’ knowledge of the official documentation.

Where to put the navigation XML file in a multi-module project?

Multi-module projects is a recommended way how to structure new apps. Advantages are faster…

After 2.5 years of working in my own company, I’m ready for an additional project as a Senior Android Developer, Dev Lead or DevRel. I’m inviting recruiters to fill my inbox :-) This blogpost provides some background.

What about Settle Up?

My company Step Up Labs is healthy. We managed to release completely rewritten Android and Windows apps with new features, professional design, and robust backend. We had a hiccup a year ago when many users were surprised by many changes at once and our rating went down. But we engaged in conversations with our users, listened to their feedback and improved the app…

Vzali jsme se s Bára Drbohlavová 8.9.2018. Oba organizujeme konference pro mnohem víc lidí, tak nám přišla jednodenní akce pro 100 lidí jako brnkačka. V duchu shrnujících postů z DevFestu a mDevCampu sepisuji i report z WeddingConu. Může se hodit, pokud uvažujete o vlastní svatbě.

Měníme status na Facebooku pomocí NFC prstýnků

První kroky

Svatbu jsme probírali nejdřív na Islandu rámcově a ve Vietnamu jsem žádal o ruku. Hned jsme začali řešit první detaily a ve Vietnamu si nechali za hubičku vyrobit šaty a oblek na míru. Stejně jako u konferencí, první krok bylo založit battleplán. Je to sdílený Google spreadsheet, kde jsou jednotlivé taby pro různé aspekty (termín…

I helped to organize mDevCamp — a conference about mobile development which took place on June 15, 2018. I was responsible for the conference gamification. This year, we were inspired by a popular topic of cryptocurrencies and created a system simulating a crypto exchange for attendees. The game was a big success: 520 out of 750 attendees participated. In this post, I will explain our system design, open-source code, share some statistics and show how it could be improved.

TV interface of the game


At first, we were looking at various cryptoexchanges like Coinbase and Kraken and figured out the MVP which would fit the…

We started organizing DevFest in February according to the vision described in this article. The event is over now, so let’s see how it all worked out.


The move back to Prague was a good call. We had 500 attendees! 38% of attendees were not from Prague. The event sold out one day before the event. But it wasn’t easy for us because most of the tickets were sold in the last two weeks:

Number of registered tickets in time

First day talks, second day workshops

On average, attendees rated the talks “great” in our feedback form. We are really proud of our selection of speakers. We also used tablets to collect…

We have been working hard for the past year to bring you the new Settle Up. We decided to redesign the app and change the underlying technology, so it’s rewritten from scratch. Let’s dive deep into most of the changes.

New design and colors

That is probably the most visible aspect, because we now have a new design from a professional designer Michal Feltl. It follows the Material Design Guidelines strictly and adds some playfulness. The main concept is that you should be able to choose a different color for each group. The whole app changes color based on which…

Null safety is one of the best features of Kotlin. It makes you think about nullability on the language level so you can avoid many hidden NullPointerExceptions which are so common in Java. However, when you automatically convert your Java code into Kotlin, you can see a lot of !! symbols there. It looks like you should not have any !! in your code unless it’s a quick prototype. And I believe it’s true, because !! basically means “you have a potentially unhandled KotlinNullPointerException here”. Plus it looks hacky.

Kotlin has some clever mechanisms how to avoid this, but figuring…

David Vávra

Google Developer Expert for Android, Founder & CEO at Step Up Labs, early adopter.

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