Facebook is walking a tightrope with its API; they need to expose enough functionality so we can develop compelling services, but guard against malicious applications that could degrade the Facebook user experience, for example by flooding people with spam.

The API is a compromise between these two conflicting goals, and I’m going to cover what you can and can’t do. Overall, I’ve been able to see some patterns in the decisions they’ve made about what to expose, and how to expose it:

• Apps can only see what the logged-in user can see.
• Getting access to any information held by Facebook requires the user to go through a screen where they temporarily authorize, or permanently add, the application.
• The Facebook team are very conservative about letting applications change data held by Facebook. Most of the API is focused on reading data, there’s only a few specific places where you can alter data:

1. Adding an application box to the user’s profile. This gives the app a small sandbox to draw something interesting, but the content has to be statically set by the application, and then is stored by Facebook. The only time you can update it is if the user takes an action that involves your application, there’s no way to fetch it dynamically. If there’s some scripts within the markup you place in the box, they aren’t run unless the user clicks on it in the profile.
2. Publish an item on the feed. You can only publish to the current user’s feed, and the app is has time limits on how often it may call it, once every 12 hours for stories, 10 times a 48 hour period for actions.
3. Send notifications or emails to friends. Again, there’s limits on how many you can send in a day, up to 10 emails and 40 emails and notifications. The user also has to go through an additional screen to authorize emails.
4. Photo upload. An app must get additional permission from the user before it’s allowed to upload photos. Each application only has to do this once per user, the permission is granted permanently.
5. Setting the user’s status text. This is another operation that requires an additional step of seeking permission from the user.

• There’s no way to use the API to affect anything not covered here, such as adding information to group or event pages.

There is an alternative way to perform some actions that aren’t covered by the API, by hand-crafting Facebook internal URLs, and redirecting to them. There’s actually a bit of official documentation on this here.

Funhouse Photo User Count: 1493 total, 123 active. Back to the more typical growth rate, which is strong evidence the strong growth of the last few days was caused by Columbus Day boredom.

Event Connector User Count: 40 total, 10 active. Not much happening here so far, I’m reaching out to some more event promoters to get them to give it a go.

After growing so linearly it was almost creepy, Funhouse Photo gained over 200 users since yesterday. And I have no clue why! I’ve been searching to see if it got mentioned or reviewed somewhere, but I’m drawing a blank. I don’t get much information from Facebook about how people found the app, I’d need to manually build in some tracking myself, and I’d probably not be able to get much information about the referring page anyway since Facebook does so much redirection.

Oh, I did just have a thought. It was Columbus Day yesterday, I bet there was a lot of bored people looking for something fun to do on Facebook. Interesting, probably won’t translate into a long-term trend if that’s the case.

I wish I could have made it to Graphing Social Patterns, the Facebook developer conference. From the notes, it looks like Danny Sullivan is thinking along the same lines as me with social search; wanting to use your friends’ browsing habits to give you more focused results.

Funhouse Photo User Count: 1466 total, 344 active. Probably a Columbus Day blip, but nice to see a growth spike.

Event Connector User Count: 39 total, 5 active. Still working with Emile and Tim from New Media Expo to arrange some distribution of their connector, but not much activity otherwise.

After three submissions, and two rejections, Event Connector was finally accepted into the directory. I was initially rejected for not having an icon, which was my fault, but the second rejection was for displaying secret events, which I never understood and filed a bug on. I didn’t make any changes to fix that, since I had no clue what they issue was, but I resubmitted it unchanged and this time it was approved!

I’ve started to get some more users through the listing, and had a really helpful conversation with Nikki Sullivan that led me to make changes to the UI. I added some links to reach the main page, with a sidebar icon for the app as well as a link in the title of the profile box. I love getting this sort of help, thanks Nikki!

I’m still unsure who’s going to be using the app. My initial plan was to target promoters, and have them spread the app as a flyer for a particular event. It looks like it’s more popular with guests so far, and they’re using it as a hub to view and investigate all their events. If that’s the direction my users are taking me, that suggests some extra features:

• A profile button that displays all the upcoming events someone is attending.
• List all the events that your friends are going to.
• A cleaner, more compact view of all the events.

This would take it in the direction of being a SuperEvent organizer, rather than the promotional tool I was imagining it to be. I’ll be thinking about this some more, and trying to understand how people are using it.

Funhouse Photo User Count: 1,154 total, 59 active. Much as before, I’ve made no changes in the last two weeks, and the growth rate remains the same.

Event Connector User Count: 27 total, 15 active. After its first day in the directory, it’s picked up a some users, though I haven’t seen it used to promote an event yet.

I stumbled into thinking about organizing conferences online by accident. I was looking for a way to see which of my friends were attending Defrag, there wasn’t anything out there that let me see that, and so I built a Facebook app to solve my problem.

That went down well, so I generalized it into Event Connector, and went looking for more events to try it on. I want to see if its simple services solve painful problems for guests and organizers, which types of events are the best fit, and build a relationship with some early-adopting event promoters to learn more about the market.

I’m also thinking about the folks over at EventVue. They’re building a much more advanced system, a suite of online tools to let conference organizers offer guests lots of interesting services. They’re a sharp team, just graduated from TechStars with an angel round under their belt, and we’ve chatted in the past about their work. I’d like to be able to back up any advice I offer them with some concrete data, and the only way to get that is to try a few things in the wild.

As an attendee, here’s my personal pain-points with conferences:

I don’t know who’s going. I usually end up bringing up conferences in conversations or emails with acquaintances in the runup to a show, but I don’t always remember, and I don’t ask everyone. Meeting old friends and connections is a big reason for going to conferences to me, so anything that increases my chances solves a big problem.

Nobody else knows I’m going. For both practical reasons, and yes, status reasons sometimes, it’s a benefit to me if I can advertise my attendance at a show. If I’m speaking, or doing something else prestigious there, I would like people to know that too. It’s even useful for past conferences, think of the strings of ribbons people wear to SIGGRAPH to demonstrate they’re old-timers.

It’s hard to organize informal get-togethers. Birds-of-a-feather sessions are usually the most valuable part of the show, but often it can be hard to arrange them, hear about them, and understand which are likely to be most useful.

Discussions finish at the end of a session. Of course, small groups usually peel off and continue chatting about ideas that came up from a presentation, but these are fragmented and there’s no process beyond arranging to start an email thread to continue them. I’d love to have a online area for each session where questions and discussions could go on past the conference.

Funhouse Photo User Count: 1,143 total, 60 active. Continuing the trend of gradual growth.

Event Connector User Count: 19 total. I reached out to a few prominent people in the tradeshow world like Rich Westerfield, Sue Pelletier and Tim Bourquin. Rich put up a blog post which was picked up by a few other blogs, and that’s helped boost my total. The directory submission is in the queue again. My goal is to get at least one more event using a connector within the next week.

It’s really important to collect a few important statistics to measure a project’s progress. One of my goals is to create an app that has over 25,000 users, an arbitrary number but one that’s high enough to use as evidence that it appeals to people outside the early-adopter geek crowd.

I’ve been collecting daily statistics since I launched Funhouse Photo, and I wanted to do analysis on them. At the top is a static image of the graph I created using Google Spreadsheets, and I’ve included a live link below. I’d never used the Google office products before, and I was pleasantly surprised. They’ve done a good job replicating the usability of a desktop app on the web. Unfortunately my OS X Firefox 2.0.4 wouldn’t display the graphs correctly, and neither would Safari. Luckily, if strangely, FF 2.0.4 on Vista did work, so I was able to complete the job using that.

Visualizing the data immediately gave me two important insights:

1. There’s a knee in the total user curve, and that corresponds to my introduction of asynchronous image loading. This is strong evidence that it’s something that puts users off using the app, and so makes improving that seem important.
2. It’s hard to see any other changes in the adoption curve’s slope. This means that all the other upgrades I’ve done to the app haven’t had an impact. Adding more effects, including notifications in user’s feeds and the profile button all failed to increase adoption. Getting a positive review didn’t result in more users.

Facebook recently introduced a "More Stats" option for all apps. This gives you access to a lot more information about the number of adds and removes, as well as a sample of the actual urls people are visiting. There’s no way to download the history, so for now I’ll keep manually entering them every day.

Funhouse Photo User Count: 1142 total, 74 active. Still the same slow growth trend. Extrapolating, the entire planet should be using the app in around 411,000 years.

Event Connector User Count: 11 total. I’m still waiting to hear back on the bug I filed about secret events, and on my resubmission to the directory, but I am talking directly to some event organizers about trying it with their meetings.