I've attended Droidcon London and presented "ProGuard, optimizer and obfuscator in the Android SDK". You can the slides below. It was a great pleasure to talk face to face with many ProGuard users and spread the word about DexGuard.
The conference was informal and well-organized at the same time. The organizers went out of their way to get everyone talking to each other, starting with an early wake-up yell and hanging tough all the way to the after-party. The resulting vibe was unique, with many surprise encounters and with every conversation bringing new ideas and insights.
The sessions covered a wide range of topics at a fast pace. One of my personal favorites was Matthias Kappler's presentation on Gradle, which is bound to replace Maven for most Android development. "The fragment transition" by Corey Latislaw stood out with beautifully and effectively animated slides; those 6 months of work were definitely worth it for the attendees. Al Sutton, who has just joined Ouya, presented the Ouya games console with the enthusiasm and authority of an in-house expert. Of course, I couldn't miss the reverse engineering talk by David Teitelbaum -- quite effective in places, but allow me to mostly remember the conclusion that obfuscation is still the way to go. Mark Murphy's humorous presentation style can make any topic interesting, including NFC; I almost suspect he put in the technical glitches to keep the audience sharp.
Thanks to Pieter-Jan for convincing me that this was the number one conference to attend, and to the organizers for making it so.
(Picture courtesy of Matt Gaunt)