PHL Crime Mapper Post Mortem

Jan 21 2013

It’s been a little over a week since I released PHL Crime Mapper and the response has been beyond my wildest dreams. Here’s a few select quotes that made me proud:

"…a handy tool…"

"…gives easiest look yet at crimes by neighborhood"

"…wins points for simplicity…"


"…handy interface for seeing where serious crimes are being committed."

"…crisp, easy to use…the simplicity and refinement of design is excellent."

I was even on the radio to talk about it!

I like seeing words like “handy” and “simplicity” because that’s definitely what I was going for. The app strives to do one thing and hopefully do it well.

I also got a lot of feedback by email from community leaders and others about how they found the app useful. I didn’t think of it before, but this would be really helpful for community organizations and neighborhood watch groups. I’ll have to think about ways to get the word out to them in the future. Overall so far I’ve gotten a lot of feedback that has solidified how I should move the development forward.

A few things have been identified that need improvement. Some users had issues with using the application in so far as drawing an area and changing the date range. So tonight I added a “Draw” button to the black box on the left that explains how to use the app. In the process I actually decreased the height of that box by removing some copy from the last sentence. So that’s good.

The other thing that I have to work on is finding a date selector that is easy to use. I really like the current one but I’ve actually witnessed myself a few people having trouble figuring out how it works. I may find a different one (although I hate the calendar picker ones) or at least put a hover over the slider that explains how to use it.

Beyond that I’ve thought about some long term bigger additions that could really make the app awesome. I also have to work on making sure the codebase remains maintainable by using Backbone and maybe porting the JavaScript to CoffeeScript. I’ve never used CoffeeScript before so this would be a good way to learn.

Finally, some closing stats:

  • 30% of visits from mobile devices (including tablets). This number was a bit surprising to me, but it shouldn’t be. There was a mobile version but a healthy amount of these hits were on tablets, which the app currently doesn’t support at all, which has been been driving me crazy. I have to spend some time soon adding that support.
  • The app was viewed in 46 states and 54 countries (whoa)!
  • Internet Explorer, Chrome and Safari split 70% of the traffic down the middle, Firefox got 16% and a bucketful of other browsers got the rest. Great to see Internet Explorer not in the lead.
  • Most toggled crime: Thefts. Which makes sense because there are so many of them.
  • The article accounted for about 63% of traffic, which is amazing. Interestingly enough, a fifth of that came in through the mobile version of their website.

The traffic has died down, so now it’s time to get back to work on making the application better long term.

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Dave Walk is a software developer, basketball nerd and wannabe runner living in Philadelphia. He enjoys constantly learning and creating solutions with Go, JavaScript and Python. This is his website.