Here is my roundup of the second day of DroidconBKK - a little late but I was a bit overwhelmed with information and it took a while to process it all.
The second day focused more on practical applications of the various technologies, case studies from a number of local startups (of which there seem to be a quite a few, Bangkok has a very active application development community). If you were interested in building your own startup it would have been a great opportunity to see different approaches to building the infrastructure.
After the first day, and after having a chance to play with Android Things overnight I was more interested in the sessions covering Firebase and the various design and development tools available for Android. It's been a while since I have done any application development for Android, my focus at my previous job was porting the platform - not writing applications for it, so getting a fresh look at what's available was good.
My focus has definitely been on Android Things though and the possibilities available with the various Firebase APIs. Android Things gives you access to the hardware through the Peripheral I/O manager so you can use all the IO pins on the Raspberry Pi. Android and the Raspberry Pi is a probably a bit of overkill for a simple sensor or controller but as a hub for a bunch of smaller, cheaper sensors it makes a lot of sense.
There are a number of Firebase APIs that would help with this - the Realtime Database for storing incoming data and configuration, Cloud Messaging for notifications and Cloud Functions (which support acting as HTTP webhook inputs) for triggering events from outside sources. Add to this the standard Android APIs that are availabe like the Nearby API for detecting and communicating with other Android devices in range and the Cast API for providing a second screen without needing a physical screen attached to the device and you have the potential for an easily configurable, cloud backed sensor hub.
The idea is still in its infancy but the general goal is to add a few LEDs and buttons to the Pi for basic interaction and a radio transceiver of some sort (an NRF24L01+ or a RFM69 for example) - this would allow me to distribute a lot of cheap, low power sensors around the house and let the Pi manage them all and feed the data into my local MQTT server or into the cloud.
My first step though is to start playing with Android Things and seeing what can really be done with it (I was similarly interested in the Windows 10 IoT Core release for the Pi but it turned out to be a bit dissapointing).
I am really glad I went to Droidcon - all in all it was a very valuable experience. If you get the chance to get to one I highly recommend it even if Android isn't your primary interest - just being exposed to working examples and different approaches can kick start the idea process.