Google Developer Days (GDD) Krakow 2017

After 6 years without Google Developer Days, they come back. I was never present at past Google Developer Days, I was only at Devfests, therefore I was excited that they come back. I have got a discounted ticket because I am part of GDG and it took place in Krakow which is not far from Prague.


The venue was great, there were nice decorations only for the event, like stickers on the stairs, branded bean bags, posters on the columns and huge flags. And you can see the Wawel Castle directly from the windows. Krakow felt like home to me, it is really similar to Prague.

Branded Chill-out zone
Wawel Castle

There was a constant supply of a variety of juices, water, and great coffee. The place was full of organizers. All the attendees got a shirt and stickers. At the end, all the SWAG was given out to attendees. We also got Android Things Pico Pro Maker Kit as a gift. There were a few hours long queue for Android Things gift which makes no sense to me because at the end of the day I got a gift in a no time.

Android Things gift voucher
Queue for Android Things

The food was good, but I missed some proper meat and the packaging fascinated me. Some of the desserts, for example, were distributed in glass jars and the fork and spoon were wooden. Wifi at the venue was stable and quick enough (when you are not at a workshop).

Internet at the venue

We booked an inexpensive accommodation via Booking. We wanted to live in walking distance to the Congress center, but the accommodation wasn’t fixed to one place, so we lived further away. We loved that we picked keys from the box with the key code and never saw the renter. The place was neat and the Internet was quicker than expected. Prices in Krakow were lower than in Prague, same applies to Uber which we used extensively.

Internet at accommodation



Most of the talks were recorded so you can watch them, here is a short summary of talks which I found interesting.

  • Keynote

The keynote was very professional. The talks were short and introduced topics in further sessions.

The also talked about Udacity scholarships (

Keynote animation
  • Progressive Web Apps

Introduction to PWA. What problems does it solve and how it works.

  • Google Developer Experts & Summer of code and Code-in

Those were community sessions which were not recorded. Google developer Experts ( program was introduced and some experiences from Experts and expectations from Google were clarified.

Summer of code ( is a program for students which want to spend their summer coding at some open source project.

Google Code-in ( is a program for pre-university students which introduces them to Open source world.

  • AR core

The augmented reality for Android, which was introduced last week. I am looking forward to trying it.

  • Google Cloud IoT Core Technical Deep Dive

Some example usages of Android Things and Google Cloud. Which tools to use and how to connect them.

Day 2

  • Keynote

The second keynote was about GCP and voice assistant. New voice assistant features and mind blowing (e.g. you define conditions and then you may ask on it — I will swim in the lake when the temperature is above 20°; May I swim in the lake now?).

  • Machine Learning with TensorFlow

I know a lot about TensorFlow and I have seen a lot of talks explaining it and I think this one is the best of them.

  • Containers, Kubernetes and Google Cloud

I love Docker and Kubernetes. This talk shows how to use them with a very smooth and explaining demo — probably because of that the technology works so well ;)

  • Hands-on Running A TensorFlow Model on Android

This was one of the workshops which are not recorded. Which does not matter because we followed When installing the dependencies we, of course, crashed the wifi. The workshop was so full that plenty of people has to sit on the ground (including me).

I helped a few people with Tensorflow and created pull-request to the Codelab ( so now it may be executed in Docker simply.

I was introduced to neural net called Mobile Net which is Inception v3 optimized for mobile devices. I have also found out that deploying models to Android is now much simpler, good work.

Full Tensorflow workshop
  • Intro to Deep Mind

I know a lot about Deep Mind and their research, but for people who know nothing about them, this is good starting point.

  • Closing Keynote

The closing keynote was about the size of the conference and about the diversity and problems connected with bias. The speaker had some problems with the video projection (she was a director of YouTube), which was really funny for the audience.

Notable booths

All videos —


We traveled with FlixBus which was part of the ticket. It was an 8 hours travel. I was prepared with offline Coursera ( — which I really love) and offline Breaking Bad episodes on Netflix (which I am finishing). Because of which the travel was really productive and fun. There was free Wi-fi during whole travel, but I did not use it because ping was over half a second.

On the way back I did not manage to get a breakfast (too sleepy) and after many hours we finally stopped for a break. Sad thing was that the stop took place in the middle of nowhere at the Bus station in Olomouc.



We started with a party which was a night before the conference and it was mainly for Google Developer Experts, and It was a great one. There was bowling, great food, dance floor and VIP area for GDEs.


After first day of the conference there was an afterparty. I have met some friends from other countries which I did not see for a while. There were free drinks, mini golf, Jenga, and dance floor with ball pools which were never ending fun, because there were huge ball fights between the pools each two seconds.

Ball Pool

After the end of the conference we had a quick GDG Summit, where we had some presentations about success stories and experience of some GDG groups and then we continued with networking.

GDG Summit drinks


Google wanted to have around 50% women and I think that he almost succeeded. The event was perfectly organized and it was fun. As for the technical part, I liked some talks, but I have heard most of the things at Google IO 2017 and I would appreciate some talks about the internals not only about the APIs and some harder topics.

And you know, you should try Kotlin for Android dev…