Carpé Cocoa

A little over a month ago, the appMobi team was sitting outside around a table at our favorite bar/restaurant, enjoying the warm summer weather and a cold drink. We had just finished our last meeting before I headed off to WWDC, and we were sharing pictures on our iPhones by passing them around the table. That was when we realized “there should be an app for this!”

Sure, there are apps that let you upload images to Facebook, Flickr, and all sorts of other places…. Sure, you can email a picture, and with iPhone OS 3.0 coming soon even MMS one (assuming you’re not in the US and don’t care about quality). There are even apps that let you share photos on the spot, phone-to-phone, but only if you are all on the same WiFi network.

We knew that 3.0 would be out soon, possibly as soon as WWDC. We also knew that 3.0 had peer-to-peer Bluetooth networking support through the new GameKit framework. We decided this was a perfect opportunity to take advantage of the new OS.

I went home and got some sleep (long day and Crown don’t make for productive programming), then dived right into GameKit first thing in the morning. By lunch time I was able to share small images reliably, but clearly needed a lot of UI and networking polish. We knew we wouldn’t be the only ones with this idea, and that the quality of the app would be more important than being the first ones to market.

I spent the rest of the week polishing the prototype, and by the time I left for San Francisco had the core user interface pretty solid: translucent autohiding toolbars, a zooming and scrolling image view very much like the native Photos app, support for viewers coming and going mid-session, and more.

During the keynote at WWDC Apple announced that the 3.0 gold master was available immediately to developers. I updated from the Beta I was running and immediately found bugs in my apps. Not so much in PhotoBeamer, but in SpinSlide, which was already in the store with paying customers. I had to put PhotoBeamer aside and work on fixing the bugs in SpinSlide as quickly as possible, while attending 8+ hours of sessions and nearly as many parties through the week.

Once I got back from WWDC I was able to finish up the bug fixes and internationalization work on SpinSlide (now available in Spanish and Japanese!) and get back to work on PhotoBeamer. I updated the networking code to send arbitrary size images reliably, added a camera button to allow taking pictures right in the app, and continued with the visual polish, adding activity spinners and a status view with separate progress bars for each client and a multi-line status area to ensure the user has a chance to read messages as they come up. I created a free version called BeamCatcher and fought through some issues with my build scripts, and added the ability for the clients to save images to their Photo Album, but only if the sender allows.

A few beta test sessions using multiple devices at once uncovered some more bugs that were addressed, and the arrival of the 3GS showed some more room for improvement in both the networking and image display code, thanks to the larger images. Most importantly, I discovered how to detect when Bluetooth is not enabled without using the built-in peer picker controller, which doesn’t fit well with the PhotoBeamer app flow.

After all that, and an unusually long review at Apple (likely due to the massive influx of new and updated apps around 3.0), both PhotoBeamer and BeamCatcher went live June 12th. Get PhotoBeamer to share your pictures. If your friends won’t spring for the full app, they can download BeamCatcher to view for free.