Android Leadership

Effective mobile engineering

Building a mobile app isn’t only about coding. It is the entire process, automations and testing, code architecture and of course people behind all of that. I was writing about all of this in my latest blog post Fail safe, not fast.

Today you can also see the video from my presentation at Mobiconf 2018.
I was talking about our experiences from building mobile apps at Azimo. So if you are curious about how the relatively small team can build effectively an app for the global market, I invite you to watch this:

I also had a chance to share my insight during this year’s Google DevFest in Coimbra, Portugal. Slides from the updated presentation can be found on my SpeakerDeck.

I hope you’ll enjoy it. 🍿📺
Soon I’ll publish more posts about doing effective mobile engineering. Stay in touch!


Multi-module Android project codebase Basic setup with Dagger 2, Unit tests, jacoco report and others

Breaking the monolith to microservices is a well-known concept to make backend solutions extendable and maintainable in a scale, by bigger teams. Since mobile apps have become more complex, very often developed by teams of tens of software engineers this concept also grows in mobile platforms. There are many benefits from having apps split into modules/features/libraries:

  • features can be developed independently
  • project structure is cleaner
  • building process can be way faster (e.g., running unit tests on a module can be a matter of seconds, instead of minutes for the entire project)
  • great starting point for instant apps

In case you are struggling with multi-module Android project, I have created example app showing how to deal with things like:

  • Dependency injection with Dagger 2
  • Unit test
  • Jacoco tests coverage report

Even if those are very basic things, it can take some time to make them working correctly in multi-module Android app. To have working solutions in one place, I have created example project on my Github account. There will be more over the time (proguard, instrumentation testing, instant apps). But even at this stage it is also worth sharing.

Just take a look: MultiModuleGithubClient. Your feedback is warmly welcomed!


Random thoughts

Google I/O 18 AI everywhere

Spring geekfest goes on. Around one week ago we could see Facebook F8, taking place at San Jose’s McEnery Convention Center. Now, we are right after Google I/O 2018, probably the biggest developer and product conference (7000+ people attending), happening near to Googleplex, Mountain View. Here’s my short summary of what we could see in Shoreline Amphitheatre this year.

Artificial Intelligence Google Assistant

Google Home at home 🏠

Voice interfaces are slowly showing up in our lives. In most cases, they replace complexity of mobile devices. But there are also new features which do make sense only when they are used just with our voice.

To see quick summary where Google is with its Google Assistant take a look at this video from last Google Developers Day (starting from 33:00):


Basic Android app analytics in <60min One step towards data-driven development

Every big tech company today is data-driven. Products are more often built based on collected data rather than internal opinions. It’s very likely that in this moment some of apps on your device are serving you A/B test variants, checking how: new layout, text or even functionality affect your activity and engagement.
The biggest companies have dedicated Business Intelligence teams, their own data warehouses, custom analytics tools and big flat screens in conference rooms showing realtime charts.
And the most important — endless audience waiting to be analysed by pie charts or bars 📊.

Random thoughts

Google I/O 17 wrap up From mobile, through VR/AR, to Artificial Intelligence

May 17–19 — in that days at Shoreline Amphitheatre, Google organised the 9th edition of one of the biggest developer conference in the world — I/O17. This year I also had a great pleasure to spend that time in Mountain View with thousands of software engineers and techies from all over the globe. In this post I have collected all important announcements and experiences from this amazing 3-days festival. Just in case you would like to know what’s new coming in a world of new technology.

If you are reading this on your mobile device and want to see really short recap of Google I/O 2017 Keynote, I encourage you to check my Medium Series:


Do you remember key announcements from I/O16? Probably the most important one was transition from mobile first to AI-first.
And here we are — one year later we have voice controlled device: Google Home, Google Assistant is a fact and Machine Learning is everywhere — also in our mobile devices, cars and smartwatches (literally doing some computation without accessing the cloud solutions). Again, during I/O17 Google’s CEO Sundar Pichai spent great time of Keynote showing the progress of AI revolution.

What does it bring to us? Even more intelligence in Google Photos like best shots selection or sharing suggestions (hey, your friend is on this photo, maybe you want to send it him?). But there will be also completely new level of vision understanding — Google Lens. Camera will be able to give more context (what kind of flower we are looking at) but also take an actions (automatically apply scanned WiFi password or book cinema tickets based on poster photography). Do you still receive paper bills? Soon whole payment process can be as quick as photo shot — Google Lens and Google Assistant (together with partners integrations) will do the rest for you.

More AI use cases: Gmail/Inbox smart replies (do you know that 12% of responses on mobile devices are sent in this way?), AutoML — neural networks to build other neural networks, so we can spend our time to think what to achieve, not how. Even more cloud AI services, partnerships and benefits for the best researchers. And new TPU, Google’s hardware to do cloud Machine Learning even faster.
Those and many other AI-initiatives finally have new home on the Internet:

Google Assistant

Number of announcements and talks related to voice/text interfaces during I/O17 shows that it’s not only an app but completely new ecosystem which can work across all of your mobile devices. Google Assistant is available on Google Home, smartphones (including iPhones!), smartwatches, TVs and soon also in cars and any other pieces of hardware (thanks to Android Things).
Finally besides just talking, you can communicate with Assistant through text messages (so you can use it outside, in crowded places without looking weird 😉). And response will come in the best possible format — if the words are not enough, Assistant will use one of your screens (phone, TV, tablet) to display intended informations. So you can ask Google Home for direction to your favourite store and map will be sent to your mobile phone or car!

There is of course much more — hands-free calling, multilingual support, bluetooth, proactive notifications (Assistant will be able to back to you with informations in the best possible time, e.g. when your flight is delayed or traffic jam can make you late on scheduled meeting).
But probably the biggest announcement here is that Google Assistant now supports transactions and payments 💸.
Why is it so important? The numbers show that most of people really don’t like any kind of input fields — the biggest drop-offs happen while entering payment details or during sign-up process. And it makes sense, we would like to order food or send some money to friends without filling another form (because we already did this so many times in the past!). And this is where Assistant can help with, especially for first-timers. With a simple permission request it can provide all needed data (user or payment details) to our app or platform, so user won’t need to care about it anymore.

Android O

Even if we still don’t know if it’ll be Oreo or Oatmeal Cookie, there are a couple great things which are coming to our mobile devices. Full picture-in-picture support will give you possibility to keep video conversation while looking at calendar or notes. Even more intelligence — to improve battery, security and user experience. With Smart Selection your device knows the meaning of text so it’ll be able to suggest Maps for selected address or dialer for phone number. Who knows, maybe when this API is opened, you will be able to send some money to your friend just by selecting his name?

O comes with another great initiative — Android Go. With fast growing global market for mobile, especially in emerging countries, we need to have system which works well on slower devices and limited data connection.And Go is an adaptation of Android O to meet those requirements — to make our apps truly global.

Side note: if you are Web developer it can be also very interesting for you how Twitter built their Lite app (<1MB) in Progressive Web App technology.

A lot of great announcements for developers: official support for Kotlin (and not deprecating Java in any time in the future!), Android Studio 3.0focused on speed improvements (including build process) with better debugging features to make our work even easier. And if you are just starting to build world class app, don’t miss Architecture Components — guidelines and solutions for making our code robust and scalable.

And Instant Apps — native lightweight apps which don’t require installation announced on I/O16 are now available for everyone to develop. Keep an eye on that — early partners report noticeable (double-digit) growth in purchases or content views.

For those who want to bring some intelligence directly to their apps, soon there will be TensorFlow Lite and Neural Network API — entire Machine Learning stack to make usage of our pre-trained models possibly the easiest.


Google also invests a lot of resources in Augmented and Virtual Reality. Besides new Daydream enabled devices, more apps and VR headsets there were two really interesting notes:

VPS — Visual Positioning System, Google’s extension to GPS for really precise indoor location. Thanks to Tango we’ll be able to locate inside buildings — with an addition of voice guidance it could be extremely helpful for visually-impaired people navigating through the world.

AR in education — the most exciting announcement: Tango will be actively used in education! After successful adaptation of Cardboards (more than 2 million students could take a part in virtual trips), Google announced continuation to their program — Expeditions AR (formerly Expeditions).

This time students will be able to gather around virtual objects placed in 3D space thanks to Tango enabled devices. If you want to see something very similar, I highly encourage to check one of the latest Tango integrations: ArtScience Museum in Singapore.

Everything else

There is of course much, much more. During I/O17 we could see 2 keynotes (main one and keynote for developers) and take a part in more than 150 sessions. We could see, hear or even try new YouTube 360 videos, new updates in Firebase (Crashlytics as an official crash reporter, new tools to performance analysis), Cloud for IoT, Android Auto or new smartwatches with Android 2.0.

If you would like to see literally all of announcements from 3 days of I/O17, Google published blog post with everything covered in one place:

And if you want to immerse yourself in the details, videos from all 156 sessions are available now on YouTube!

Open source your code!

Besides all of these fascinating announcements, there is one particular takeaway which I’d like to share with you. More than 1 year ago Google open sourced TensorFlow. They shared years of their experience with everyone to make Machine Learning easier. After that time there are a lot of projects from people around the world, who solve real issues without having full knowledge about theory behind TensorFlow or ML. But they have great ideas (check this inspiring video below!). By giving them proper tools, we can make all these ideas happen.

That’s why you and your dev team should share the code. Because it’s really likely that somewhere there is someone who you could help with making the world a better place. We, the tech team behind Azimo do it.

Do you?

Android PerfMatters

FrameMetrics — realtime app smoothness tracking

A couple months ago, when Android Nougat was announced, among new features like Multi-window, enhanced notifications, VR support, 72 new emojis 👍 and others, there was a new addition to monitoring tools: Frame Metrics API.

Android Dagger 2

Activities Subcomponents Multibinding in Dagger 2

A couple months ago, during MCE³ conference, Gregory Kick in his presentation showed a new concept of providing Subcomponents (e.g. to Activities). New approach should give us a way to create ActivitySubcomponent without having AppComponent object reference (which used to be a factory for Activities Subcomponents).
To make it real we had to wait for a new release of Dagger: version 2.7.

Android Dagger 2

Building UserScope with Dagger2

In Azimo Android app we use Dagger 2 as a framework for Dependency Injection to make our code architecture clean and easy to scale. Like in our previous post we would like to share our experience so today I’ll show how to avoid issues and build custom UserScope which can be used in production app.


Custom scopes in Dagger 2 can give better control on dependencies which should live unusual amount of time (different than application and screen lifetime). But to implement it properly in Android app we need to keep in mind things like: scope cannot live longer than application process, process can be killed by system and restored in the middle of user flow with new objects instances.

Example source code is available here: Dagger 2 recipes: UserScope.

Android Dagger 2 PerfMatters

Dagger 2 on production — reducing methods count

Dagger 2 — fully static, compile-time dependency injection framework is a backbone of code architecture in Azimo Android app. We already know that with growing dev team clean code structure is one of the most important things in every project. Initialisation/usage separation, easier testing (unit or functional), better scalability —those are just a few of the benefits that come from use of dependency injection framework like Dagger 2.